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 Tracliyscelis, Lat. 

 inserted among other heteromerous insects, and separated 

 from 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 Bost?ichida 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 genus Cryptophagus, as for instance, in his C.fumatus 

 (Corticariafumata, Ent. Brit.) ; and I have myself observed 

 this curious and interesting difference of the sexes in Cry- 

 j>tophagtis pallens (Tenebrio pallens, Ent. Brit.), an insect 

 by no means uncommon in England 1 . I state these cir- 



a "Detexit acutissimus Miiller pastor Odenbachensis in genere Crypto- 

 phagorum, sexui uniesse saepe quatuor, sexui alteri semper quinque articu- 

 los tarsuum in pedibus posticis; et jam observarunt, turn entomologus 

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

 parvornm Dytiscorum species, quas cum nominatis auctoribus ad genus 

 Hyphydrum referimus, solummodo anteriorum pedum habere articulos 

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

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

 torn. i. p. 299.) quurn vero in ceteris proxima. affinitate Dytiscis junga- 

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

 Gyllen. Ins. Suec. (Prasf.) Vol. i. p. v. 



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

 in lllig. Mag. iv. p. 214, allata quod tarsi postici in altero sexu pluriurn 

 specierum hujus generis tantum 4-articulati suntj hoc tamen verum esse 

 t'ji hac specie et nonnullis insequentibus olservavi," — Gyllen. Ins. Suec. 

 p. 168. 



