CENANTHE 



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Rhaebus, Calopus, Sparedrus, and Dytilus, which are 

 foreign. The genus CEdemera, as restricted by 

 Stephens, consists of those species only which have 

 the posterior femora greatly incrassated in the males, 

 the antennae long, and the elytra very much narrowed 

 behind. The type of the genus is the CEdemera 

 cuerulea (Linnaeus), a pretty little insect, found in the 

 summer months upon various flowers. 



CENANTHE (Linneeus). A genus of herbaceous 

 perennials, mostly natives of Europe, belonging to 

 Umbelliferce. They are comparatively useless plants, 

 and when grown in botanical collections are placed in 

 water or on damp rich soil. 



CENOTHERA (Linnaeus). A genus containing 

 many species of annual, biennial, and perennial herbs, 

 found in various parts of the world. They are ranged 

 in the eighth class of Linnaeus, and in the natural 

 order Onagraria. Generic character : Calyx tubular, 

 limb four-cleft ; petals inserted into the calyx ; sta- 

 mens erect or declining ; filaments awl-shaped ; 

 anthers incumbent ; style filiform ; stigma in four 

 divisions ; capsule nearly three-sided ; seeds naked. 

 The (Enotheras are in general fine flower-border 

 plants. One of the most common in old gardens 

 is that known by the vulgar name of evening prim- 

 rose, from the flowers mostly expanding immediately 

 after sunset. The roots of the CE. biennis are escu- 

 lent, and were once cultivated for the sake of their 

 tubers, which in some measure might have stood in 

 the stead of potatoes, but were superseded by the 

 introduction of that much more valuable plant. The 

 roots of this (Enothera were formerly eaten after 

 dinner, as olives now are, being esteemed incentives 

 to wine-drinking, and hence the generic name was 

 changed from Onagra, the ass-food, to CEnothera, the 

 wine- trap. 



CESTRID^E (Leach). A very interesting family 

 of dipterous insects, belonging to the section Athe- 

 ricera, having the mouth, in the winged state, quite, 

 or almost entirely, obsolete, being replaced by three 

 small tubercles, which can in nowise be applied as 

 organs of nutrition. These insects have the appear- 

 ance of large flies, with the body often very hairy, 

 and ornamented with bands of various colours like 

 the humble bees. The wings are very strong, and 

 generally extended ; the alulets are large, and con- 

 ceal the halteres ; the tarsi are terminated by two 

 ungues and two pulvilli. 



The habits of these insects are very peculiar, 

 since their larvae reside in the stomach, beneath the 

 skin, or in the frontal sinus of various quadrupeds. 

 We have, in the article BOT, given an account of 

 the habits of those species of this family which 

 attack the horse, and are known amongst farriers by 

 that name, forming the genus Gastcrophilus (Leach ; 

 Gastrus, Meigen) ; and havet herein stated, that in 

 the present article we should detail the habits of 

 the other species. 



It may, however, be observed in a general manner 

 that these insects are rarely to be observed in the 

 perfect state, although sufficiently common, and often 

 very annoying to the animals which are subject to 

 their attacks whilst larvae. Each species of the family 

 is confined to its own peculiar quadruped, and selects, 

 for the deposition of its eggs, that particular spot which 

 will be best adapted to the wants of the future larvas. 

 The ox, horse, ass, rein-deer, stag, antelope, camel, 

 sheep, hare, and rabbit, have been ascertained to be 

 subject to the attacks of these insects, which instil a 



surprising degree of alarm into these animals when 

 about to deposit their eggs. The larva;, according- to 

 the situation in which they are found, may be called 

 subcutaneous, cervical, and gastrical ; the bots belong- 

 ing to the last-named species. The larvae are thick 

 and fleshy, of a somewhat conical form, and destitute 

 of legs ; the body is composed of eleven segments, 

 exclusive of the head, and furnished with minute 

 tubercles or spines, often arranged in transverse series 

 so as to be of service in progression. The chief organs 

 of respiration are placed upon a scaly plate at the 

 extremity of the body, which is the thickest part of 

 the larva ; their situation being, however, different in 

 the gastrical species. Moreover the mouth of the 

 subcutaneous larvae is only composed of fleshy tuber- 

 cles, whereas that of the gastrical species is armed 

 with a pair of strong hooks a variation of the struc- 

 ture dependent upon the variation of habit, and which 

 requires that the larvee placed in the midst of the 

 stomach of an animal, and subject to the action of 

 the food of such animal in its passage through its 

 body, should be furnished witlv the means of holding 

 itself firmly in its place. When full fed, these larvae 

 quit their retreats and descend to the earth, in which 

 they pass the pupa state, the skins of the larvae serv- 

 ing as the cocoon of the inclosed pupa. 



The cestrus of the oxen, to which, in allusion to 

 its habits, Latreille has applied the very appropriate 

 generic name of Hypoderma (that is, living beneath 

 the skin, or subcutaneous), is one of the most renowned 

 of insects, its habits having been recorded by Virgil, 

 in his third Georgic. Dryden gives the following 

 translation of the passage in which the insect is 

 referred to : 



About the Alburnian groves, with holly green, 



Of winged insects mighty swarms are seen. 



This flying plag-ue (to mark its quality) 



CEstros the Grecians call Asilus, we 



A fierce loud buzzing breeze. Their stings draw blood, 



And drive the cattle gadding through the wood ; 



Seized with unusual pains they loudly cry - 



The claims of Dryden as a poet may be unques- 

 tionable, but he was no naturalist ; and in these few 

 lines may be seen examples of his merits and demerits. 

 For the sake of his verse he has introduced the state- 

 ment that the stings of this insect draw blood, and 

 he has employed the popular but indefinite terms 

 breeze and gadding (that is, flying from the gad-fly}. 

 Thus it would appear from this passage, that the 

 insect in question was a Tabanus, which have the 

 power of drawing blood with their powerful apparatus 

 of lancets in the mouth. But Virgil was a naturalist 

 as well as a poet, and he knew well that the effects 

 which he has described were not caused by a Tabanus, 

 but by an OEstrus. A more correct translation of 

 the passage is given by Kirby and Spence : 



Through waving groves where Selo's torrent flows, 

 And where, Alborno, thy green ilex grows, 

 Myriads of insects flutter in the gloom, 

 (CEstrus in Greece, Asilus named at Rome) 

 Fierce and of cruel hum. By the dire sound, 

 Driven from the woods and shady glens around, 

 The universal herds in terror fly ; 

 Their lowings shake the woods and shake the sky. 



Now this is precisely the effect which the presence 

 of a female cestrus (Hypoderma), buzzing about to 

 deposit her eggs, has upon a herd of oxen. Terrified, 

 with their tails in the air, or stretched out stiffly at 

 full length, they gallop about the fields, resting only 

 when they can make their way into a neighbouring 



