Ercagttrj? of Natural $? 



of Europe, as ominous of some approaching 

 calamity. The Caterpillar from which thi 

 curious insect proceeds is in the highes; 

 degree beautiful, and far surpasses in size 

 every other in this country, measuring some- 

 times near five inches in length, and being 

 of very considerable thickness. Its coloui 

 is a bright yellow j the sides being market 

 with seven elegant broad stripes or bands, of 



a mixed violet and sky-blue colour, which 

 meet on the back, and are there varied with 

 jet-black specks : on the last joint of the 

 body is a horn or process, curving over the 

 joint in the manner of a tail. This cater- 

 pillar is principally found on the potato and 

 the jessamine, those plants being its favourite 

 food. It usually changes into a chrysalis in 

 the month of September, retiring for that 

 purpose pretty deep under the surface of 'the 

 earth ; the complete insect emerging in the 

 following June or July. 



" Another peculiarity connected with the 

 history of this Moth," Mr. Westwood ob- 

 serves, " consists in its attacking bee-hives, 

 ravaging the honey, and dispersing the in- 

 habitants. It is singular that a creature 

 with only the advantage of size should dare, 

 without sting or shield, singly, to attack in 

 their strongholds these well-armed and nu- 

 merous people ; and still more singular, that 

 amongst so many thousands of bees it should 

 always contend victoriously. Huber, who 

 first noticed the fact, asks, ' May not this 

 moth the dread of superstitious people 

 also exercise a secret influence over insects, 

 and have the faculty, either by sound or 

 some other means, of paralysing their cou- 

 rage ? May not such sounds as inspire the 

 vulgar with dread be also the dread of bees ? ' 

 He also states that he was witness to the 

 curious fact that some bees, as if expecting 

 their enemy, had barricaded themselves by 

 means of a thick wall of propolis and wax, 

 completely obstructing the entrance of the 

 hive, but penetrated by passages for one or 

 two workers at a tune ; thus instructing us, 

 that at the period when the moth appears, 

 when also wasps and robber bees attack the 

 hive, it is advantageous to narrow the en- 

 trances to it, so as to prevent the depreda- 

 tions of these obnoxious insects. The species 

 appears to be distributed over the greater 

 part of England and Scotland, and many 

 specimens are annually obtained by labour- 

 ers when employed in getting up potatoes." 



ACHETID^E. A family of Orthopterous 

 insects, ordinarily called Crickets. [See 

 CKICKET.] 



ACHETJS. A name applied by M. F. 

 Cuvier to such of the Tardigrada, or Sloths, 

 as have three claws on their fore-feet. 



ACHIRUS. A genus of flat-fish, belong- 

 ing to the order Malacopterygii ; in form 

 resembling the Sole, but distinguished from 

 all other genera by the total want of pectoral 

 fins ; hence their name. The Achiri have no 

 air-bladder, and consequently remain for 

 the most part at the bottom of the sea; yet 

 their motions are there frequently very 

 rapid. They abound mostly in the East 

 and West Indies ; and as they keep near the 

 shores, they furnish a plentiful supply of 

 wholesome food to the inhabitants. The 

 most remarkable of this species is the Achirus 

 marmoratus, which has the caudal fin dis- 

 tinct from the anal and dorsal, all of which 

 are of a pale bluish-white colour, thickly 

 studded with small black spots. The flesh 

 is of a delicate flavour, and highly esteemed. 

 There is also another of the Achiri de- 

 serving notice, the Achirus pavonicus, so 

 called from the beauty of its spots, wlu'ch 

 cover the body of the fish like those on a 

 peacock's tail. 



ACIPENSER (sometimes written ACCI- 

 PENSER). A genus of fish in the Linnsean 

 system, the distinguishing characteristics of 

 which are, that the mouth is retractile and 

 destitute of teeth, and the gills have only 

 one aperture on each side. [See STURGEON.] 



ACONTIAS. A genus of Serpents, for- 

 merly confounded with the Angues, or com- 

 mon snakes, but differing from those rep- 

 tiles in certain peculiarities of osteological 

 formation, as well as in their habits j and 

 therefore Cuvier considered it necessary to 

 establish this new genus. They are cha- 

 racterized by the absence of all the bones 

 which represent the extremities of the other 

 angues, while they retain the structure of 

 the head common to those animals and the 

 lizards, and have the body similarly covered 

 with small scales only. The progressive 

 movements of the Acontias are consequently 

 very diiferent from those of common ser- 

 pents : they carry their heads and breasts 

 erect ; and, though by nature harmless and 

 even timid, when pursued they will dart 

 courageously at their assailant. There are 

 few countries in the Old World in which some 

 species of Acontias are not found ; but our 

 elder naturalists have generally confounded 

 them with serpents of a dangerously venom- 

 ous nature : hence the numerous fabulous 

 stories which are related of them by ancient 

 bdstorians. 



ACORN-SHELL. The popular name for 

 ;he Balanus and other Cirrhipeds, which in- 

 habit a tubular shell, whose base is usually 

 formed of calcareous laminae. It is always 

 bund attached to some shell or foreign body: 

 it is multivalvular, unequal, and fixed by a 

 stem, or sessile ; the valves lie parallel to each 

 other, and in a perpendicular position. The 

 inclosed animal performs its necessary func- 



