200 Prof. J. C. Schiodte on the Classification 



tion between small intestine, large intestine, and rectum. But 

 in Cebrio it is slightly winding, with powerful transverse muscles, 

 the posterior half distended so as to form first a colon of con- 

 siderable dimensions, in its posterior part furnished with many 

 small caeca, and finally a short rectum, markedly separated 

 from the former, and with powerful longitudinal muscles. 



There are four rather short (in Throscus very short and thick) 

 Malpighian vessels, of which the ends are closed and quite free, 

 although each pair is closely held together by minute tracheae. 

 They consequently do not form two loops such as are represented 

 by Leon Dufour (Ann. d. Sc. Nat. 1824, iii. pi. 2. figs. 3,4). 



Each of the testes consists of a bundle or tassel of shorter or 

 longer folliculi, which are closely united by intertwined tracheae 

 and imbedded in fat, but not enclosed in a common bag. The 

 testes are situated in the anterior portion of the abdominal 

 cavity, close to the back, over the digestive tube, which runs 

 close under them through the ring which is formed by the vasa 

 deferentia. The number of follicles in each testis is very variable: 

 in Adrastus limbatus there is only one, in Cryptohyprms quadri- 

 pustulatus nine, in Lacon murinus more than twenty ; but within 

 the natural groups their number seems to depend principally on 

 the size of the animals, so that it is upon the whole greater in 

 the larger species and less in the smaller ones. Thus, whilst 

 Diacanth'usceneus has fH'tj,D.tessellatus forty, and Agrioteslineatus 

 and obscurus fifty, Agriotes sputator has only twenty-four, Am- 

 pedus balteatus twenty, Limonius minutus nine to eleven ; again, 

 Athous niger has seventy, A. ruficaudis forty, and -^. subfuscus 

 twenty. All these numbers are approximate, as in each species 

 the number vacillates between certain limits. In Cebio the testes 

 are distinguished by their extraordinary length and slenderness ; 

 they consist of more than 100 follicles placed on short stems in 

 longitudinal rows, round the thin vas deferens, which occupies 

 the middle. 



The vasa deferentia are long, closely wound, and first extend 

 a considerable way backward, passing the vesiculse seminales, 

 whereupon they bend forward again to the point where they 

 join the ductus ejaculatorius. Near the testes they are slender, 

 but increase by degrees in thickness, without, however, usually 

 assuming very remarkable dimensions, except in species where 

 they are very short (as in Cryptohypnus quadripustulatus, Limo- 

 nius minutus, Campylus linearis) ; in species where they are very 

 long they do not become very stout (as in Ampedus sanguineus, 

 where they reach about 11*4 millims., in Diacanthus aneus, 

 where they attain 19"2 millims., in Athous ruficaudis, where the 

 length is about 11 millims.). In some species (for instance, 

 Agriotes aterrimus, Diacanthus tessellatus, Athous niger, but not 



