INTRODUCTION. 7 



Nilio, Lat. and Coccinella, L. &c., and to observe their re- 

 spective places in the latest systematic works on Entomology. 

 But two cases which affect the natural arrangement of the 

 Lamellicorn insects, though in different ways, must particu- 

 larly be mentioned. We have the genus Trachyscelk, Lat. 

 inserted among other heteromerous insects, and separated 

 fi-om Mgialia, Lat. to which it is so nearly allied both in 

 anatomy and habits. Again : it seems difficult to conceive 

 why the genus Sinodrendron, F. should be so much further 

 removed from the Bostrichidce than a Curculio, L. to 

 which these have evidently much less resemblance. 



In several cases also the number of articulations in the 

 tarsi varies even in the sexes, which peculiarity Gyllenhall 

 on the indication of Miiller observed in several species of 

 the genvis Cryptophagus, as for instance, in his Cfumatus 

 {Corticuriafumata, Ent. Brit.) ; and I have myself observed 

 this curious and interesting difference of the sexes in Cry~ 

 ptophagus pallens {Tenebrio palleiis, Ent. Brit.), an insect 

 by no means uncommon in England^. I state these cir- 



* « Detexit acutlssimus Miiller pastor Odenbachensis in genere Crypto-r 

 phagorum, sexui uni esse saepe quatuor, sexui alter! semper quirique articu- 

 los tarsuum in pedibus posticisj et jam observarunt, turn entomologus 

 consummatissimus Dom. Doct. Illiger, turn laudatus Miiller, plurimas 

 parvorum Dytiscorum species, quas cum nominatis auctoribus ad genus 

 Hypbydrum referimus, soliimmodo anteriorum pedum habere articulos 

 tarsuum quatuor, postici vero pedum pans quinque, unde Cel. Illiger 

 ex hoc genere peculiarem subdivisionem jure formavit; (vid. lUig. Mag. 

 tom. i. p. 299.) quum vero in ceteris proxima affinitale Dytiscis junga- 

 tur illud genus, proxime ab eis id inserui notata tantum hac diversitate." 

 Gyllen. Ins, Suec. (Praef.) Vol. i. p. v. 



Again: " Singularis valde et inexspeetata est observatio a Dom. Miiller 

 in Illig. Mag. iv. p. 214, allata quod tarsi postici in altero sexu plurium 

 specierum hujus generis tantum 4-articulati sunt; hoc tamen verum esse 

 in hac specie et nonnullis insequentibus observavi,"—Gy\\en, Ins. Suee, 

 p. 168. 



