Byrrhidce.] CLAVICORNIA. 365 



BYRRHID^l. 



This family contains about twenty genera, and a hundred and fifty 

 species ; they are widely distributed both in tropical and temperate 

 countries, and a certain number are found as far north as Alaska and 

 Siberia ; they are oval, convex insects, with the head retracted in all the 

 genera, except Nosodcndron, and the antennae usually 11-jointed, rarely 

 10-jointed, the last joints forming a more or less elongate club in all 

 our genera; la' rum distinct; anterior coxal cavities open behind; 

 prosternum somewhat prolonged behind; mesosternum small, metasternum 

 short and broad ; elytra covering abdomen ; abdomen with five segments, 

 the first three being sometimes connate ; legs short and stout, strongly 

 retractile, tibise dilated, and usually altogether or in part sulcate 

 externally for the reception of the tarsi ; tarsi 5-jointed, with the last joint 

 elongate, heteromerous in Aspidiphorus (Conipora) : with regard to the 

 latter genus I have followed Mr. Matthews in placing it with the 

 Byrrhidaa, rather than together with ^ Sphindus in a separate family 

 Sphindidas, as is done by Keitter and others, as the formation of the 

 external skeleton seems certainly to prove its alliance with the present 

 family ; at the same time *ts position can hardly be said to be quite 

 settled, and it does not quite agree with the Byrrhidae in all the 

 characters above mentioned ; Thomson regards it as a separate family 

 which he calls Coniporidoe ; many authors place the genus together with 

 Sphindus under the Bostrychidse. Limniclius is also regarded by some 

 authors as belonging to a separate family Limnichidse. Great confusion 

 is now caused by some of the continental authors, who apply the name 

 Byrrhidse to Anobium (jByrrltus, Geoff.) and its allies, and alter the 

 name of Byrrhidae as it at present s-tands to Cistelidse; in the catalogue 

 of Heyden, Reitter, and Weise there seems to be a reductio ad absurdvm, 

 as on page 90 Byrrhus is retained as the generic name of B. pilula 

 and its allies under the Cistelidae, whereas the Byrrhidas on page 122 

 do not contain a genus Byrrhus at all. 



The larva of the ByrrhidEe, as typified by S. pilula, are fleshy, and may be recog- 

 nized by the large size of the prothorax, and of the last two segments of the abdomen ; 

 the head is corneous, with two ocelli on each side, and the antenna? arc very short 

 3- or 2-jointed ; the prothorax is as long as the two following segments united, and is 

 covered with a hard corneous scutum ; the abdominal segments are nine in number, 

 the ninth being furnished with two appendages which are used for progression ; the 

 meso- and metathorax and the first seven abdominal segments are membranous, and 

 the last two are harder, very large, and deflexed ; the legs are moderate in length, 

 with very short tarsi terminated by a simple claw ; the larva of J5. pihila is figured by 

 Westwood (Classific. i. 175, fig. 17, 17), and also by Ctiapuis et Candeze (I.e., 

 PI. iii. f. 4); it is found in the ground under turf, or crawling on the surface,- it is 

 about three-quarters of an inch long. 



(The genus Nosoflendron, represented by the single European genus 

 N.fasciculare, used to be included in all our British lists, on the autho- 

 rity of specimens taken byLeach in Devonshire, and Hope at Southend, 

 Essex ; it is figured by Curtis (British Entomology, fig. 246) ; from the 



