i:es 



XYLOCARPUS. 



XYLOPHAC-r. 



1258 



XYLOCARPUS (from v\oi>, wood, and mfrrrAs, fruit), a genus of 

 Plants belonging to the natural order Mdiacea. This genus, with 

 Penoonia, has been referred by Aublet and other botanists to the 

 genus Carapa. [CABAPA.] 



XYLO'COPA ( Wood-Cutters), a genus of Insects of the sub-family 

 Scopulipides, Latreille, or Anthophorides. The insects composing it 

 are characterised by the very thick coating of hairs upon the hind 

 leg? of the females, which constitute pollen-brushes. The basal joint 

 of the posterior tarsi usually exhibits its extremity angularly pro- 

 duced. They have no pollen-plates, and the abdomen is destitute of 

 a ventral pollen-brush. The wings have usually three perfect snb- 

 margiual cells; the third joint of the antenna; is frequently long and 

 elevate, being very slender at the base ; the mouth is sometimes con- 

 siderably developed. Notwithstanding the shortness of the wings and 

 the comparative bulk of the body, these insects fly with much strength 

 and activity, and with a loud buzzing noise. 



The sexes differ considerably (in many cases), both in colour and 

 structure ; the males in some cases having very long antenna', while 

 in others the posterior femora are much thickened, and in a few the 

 tarsi of the intermediate legs are furnished with curious brushes of 

 hair. The face is frequently of a pale yellow-colour. The females 

 are usually of darker and more obscure- colours than the males. They 

 form their nests in crevices of old walls or in banks exposed to the 

 BUD. Their cells are composed of earth and are very smooth in the 

 inside, and the mouth of the nest is closed with the same material. 



The wings of the Xylocopa, or (as they are frequently termed) 

 Carpenter-Bees, are most frequently (although not always) black, with 

 a fine purple or violet gloss. The habits, &c. of a French species, the 

 X. violated, have been carefully studied. The females of this species 

 appear in the spring, and select posts, palings, &c. in which they 

 construct burrows from 12 to 15 inches in length, and rather more 

 than half an inch in diameter. The two extremities of the tunnel are 

 covered, leaving a narrow passage at each end. Upon the completion 

 of these works, they deposit an egg at the bottom, with a due supply 

 of pollen-paste ; the whole is then covered with a layer of agglutina- 

 ted sawdust, formed during the construction of the burrow. The 

 layer thus formed is made to act in the double capacity of a roof for 

 the original cell and a floor for another above it. In this manner 

 about twelve cells are usually formed. When the larvae are full 

 grown, they assume the pupa state, head downwards, so as to allow 

 the lowermost and oldest to make its way out of the bottom of the 

 burrow as soon as its wings are sufficiently developed, and which 

 consequently occurs sooner than in those in the upper cells. 



The males of some of the larger species, X. latipes, and some others 

 not yet properly described, have the fore-legs gi-eatly dilated. An 

 excellent history of the Xylocopa is given by Reaumur ('M(Sm.,' 

 torn, vl, me'm. iv.). 



XYLO'MA, a genus of Fungi approaching in character Splunria. 

 From this genus it was formerly distinguished by negative characters, 

 such as the sporidia not being external All the species which were 

 referred to this genus are placed by Berkeley under the genera Spharia, 

 Hyitcriwn, Phacidium, &c. The most common species of this genus 

 are found on the decaying leaves of trees, especially of the sycamore 

 and maple, the leaves of which are frequently covered with black 

 spots, the results of the attacks of Fungi formerly referred to this 

 genus. 



XYLOMELON, or XYLOMELUM. [PROTEACE*.] 



XYLOPHAOA. [PHOLADID.E.] 



XYLO'PHAGI ( Waod-Halen), a family of Insects of the order 

 Coleoptcra Tetramera : they are distinguished from the family 

 which usually precedes them (the Weevils) by the absence of a 

 proboscis. [CcRCULlo.] The antenna; are thickened towards their 

 extremities, or perforated from the base ; always short, and usually 

 composed of less than eleven joints. The tarsi, which in some cases 

 appear to be 5-jointed, are usually entire, the penultimate joint being 

 dilated in some species and cordiform in others. In the latter case 

 the antenna: are always terminated by a club, either solid and ovoid 

 or trifoliate, and the palpi are short and conical. These insects gene- 

 rally live in wood, which is perforated and channelled in various 

 directions by their larva;. Some species are destructive to pines and 

 firg, some to olives, while others feed on Funyi. 



This family is divisible into three sections. 



Section I. Those which have the antenna! composed of ten joints 

 at least, either terminated in a thick club, generally solid, or having 

 three elongated plates, or forming a cylindric and perfoliate club from 

 the base ; the palpi are conical ; the anterior tibiae in the majority are 

 toothed and armed with a strong hook, and the tarsi generally have 

 the penultimate joint bi-lobcd. Some have the palpi very short, and 

 the antennae terminated in a solid or trilamellar mass, preceded by 

 five joints at the least. 



These Xytojihagi compose the genus Scotytus, Geoffroy. 



In some the penultimate tarsal joint is U-lobated, and the antenna; 

 have seven or eight joints preceding the club. Scotytui proper (Eccop- 

 tognster. Herb/it) baa the antenna! straight and naked, the club solid 

 and very compressed, its annuli forming concentric constrictions. S. 

 dfitructor (Ili/hfinut Xcolytnt), the Common Elm-Destroying Scolytus, 

 commits great ravage* in the neighbourhood of London. This insect 

 does not appear to restrict itself to the elm, but has also been found 



HAT. HI8T. DIT. VOL. IV. 



upon the plum. Dr. Hammerschmidt, who has frequently observed 

 them in the bark of this tree (in the neighbourhood of Vienna), con- 

 siders however that it differs slightly from the S. destructor, and 

 terms it S. Pruni. Except in being smaller, there appears no other 

 distinction. 



The perfect insect or beetle is only two lines long, and the majority 

 of them are still smaller; its breadth is about half a line, and it is firm 

 and resisting to the touch. The head and throat form the principal 

 part of the body ; they are black aud shining, very finely and thickly 

 dotted, and the former (the head) covered with short yellowish gray 

 hairs. The antenna; are of a light pitch-brown, ending in a knob. 

 The wing-cases are obliquely cut off behind, and at the base near the 

 thorax somewhat hollowed : they are marked in dotted lines, and their 

 colours pitch-brown. The abdomen from the base to the apex appears 

 as if slantingly cut off, and is of a similar colour to the thorax and 

 dotted. The less are of a reddish-brown, aud the tibia dilated. The 

 larva is of a yellowish white, and has a relatively large yellow shining 

 head and a brown mouth. It ia from one to two lines long, and it 

 exhibits a whitish transparent swelling between the head aud the first 

 ring on the throat, which appears to be characteristic of the larva of 

 this species. They confine themselves to the inner bark, forming 

 winding and convoluted paths in it. Much important matter upon the 

 habits and economy of the elm-destroying Scolytus will be found in 

 the communication of Audouin and Spence upon thia subject, to the 

 respective Entomological Societies of Paris and London. 



ffylesinus, Fabr., has the club of the antenna: solid and annulated, 

 but pointed at the tip. 



Hylurgus, Latreille, has the club of the antenna; solid, globular, 

 and annulated. Hylwgus (Hylesinus) piniperda,the Scotch-Pine Black 

 Beetle, is somewhat shaggy and black ; the wiug-eases are pitch-black, 

 irregularly striated and entire at the tips; thorax anteriorly narrowed ; 

 antenna; and feet brownish red. The larva; is thick, cylindrical, milk- 

 white on the middle of the body ; the head dull yellow, as also the 

 front of the body and the anal extremity, only somewhat of a lighter 

 tint. The abode and place of propagation of the perfect insect are iu 

 the pith of the side-twigs of the pine. 



According to Bechstein, it bores through shoota of the spruce-fir 

 when there are none of the Scotch pine to be had. The eggs are laid 

 under the bark of sickly and felled pines, in the bark of which the 

 maggot resides, while it feeds on the stagnated fermented juice which 

 is found under the bark. The larva; feed on the trunks of dead or 

 dying trees, and the beetle only places her brood on healthy trees 

 when compelled by necessity to do so. In one respect the ravages of 

 this insect do less injury than those of some others, inasmuch as 

 it generally only attacks the side-twigs, leaving the leading shoot 

 untouched. 



Camptocenu, Dej. [CAMPTOCERUS.] 



Phloiotubus, Latr., differs from all the rest in the club of the antenna) 

 being formed of three long filaments. 



In others the tarsal joints, apparently five in number, are entire, aud 

 the club of tbe antenna; commences at the sixth or seventh joint. 



Toiittcus, Latr., has no notches at the sides of the thorax, and the 

 tibia are not striated. 



Platypus, Herbst, has the sides of tha thorax notched to receive 

 the femora, and the tibia are transversely striated. Fossil specimens 

 of this genus have been found embedded in amber. 



The others have the palpi large, very visible, and of unequal length ; 

 body depressed and narrowed anteriorly ; the antenna: either 2-jointed 

 (the se-ond joint being very large and irregularly shaped), or 10- 

 jointed and entirely perfoliated ; tarsi entire. 



These insects are of great rarity and very singular appearance, aud 

 are also foreign to Europe. They compose the genus Pausius, Linn. 



Pausaus proper has only two joints to the antenna', the second very 

 large and compressed. 



P. sp/tKrocerus. Professor Afzelius observed a dim phosphoric light 

 to be emitted from the singular hollow antenna; of this insecet. (' Linn; 

 Trans.,' iv., 261.) 



Ilylotorun, Dalm., composed of a single species, apparently with ocelli, 

 and with the antenna: scarcely longer than the head, and 2 -jointed. 



Ceraplerm, Swed., has the antenna; 10-jointed and perforated; 

 (Westwood in ' Trans. Linn. Soc.') 



Section II. Those which have only 10-jointed antenna;, and the 

 maxillary palpi do not taper to a point, but are either of equal thick- 

 ness throughout or dilated at the extremity. The joints of the tarsi 

 always entire. 



They are divisible into two principal genera, according to the mode 

 in which the antenna; terminate. The three terminal joints form a 

 perfoliate club in the first, or Bostrichui, Geoff. 



Bostricltus proper has the body more or less cylindrical ; the head 

 rounded, nearly globular, and capable of being received into the 

 thorax as far as the eyes ; the thorax is never less convex before, and 

 forms a kind of hood. The first two joints of the tarsi, as well as 

 the last, are elongated. The species are found iu old wood and timber. 



D. dispar (Apate ditpar, Fabr.), Xyloterus dispar, Erichson. Thia 

 Apple- Bark Beetle is very common in Austria, but rare in this country. 

 It is termed dispar because the male is not only about half tbe size of, 

 but differently formed from, the female, bearing more resemblance to 

 Anisoplia hortimla than to the bark-beetles generally. The head and 



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