INSECTS. 267 



The male individuals amongst Insects have usually two testes, 

 though there be occasionally only one, just as in the female there 

 may be only one ova-Hum. Such is the case with LithoMus where 

 the part has the form of a long tortuous canal. In the Scolopendrce 

 proper (Scol. morsitans, &c.) are different oval testes, much extended 

 in length, (described improperly by KUTORGA as epididymides) 

 which at each pointed extremity send off an efferent canal ; all these 

 canals coalesce to form a single canal which is very tortuous and 

 widens into a sac below (testiculus KuTORGA 1 ). In Scutigera there 

 are two very tortuous canals (testiculi?} present, which begin with 

 an oval sacciform expansion, and then pass into a single fine tube, 

 of great length and winding right and left with close curves ; this 

 tube opens into a canal, which as an arc connects the two efferent 

 canals each of which dilates twice into an oval vesicle 2 . In Julus 

 there are two long blind tubes, which, connected by transverse 

 canals, have the form of a ladder, and to which laterally blind sacs 

 are appended ; these sacs may be considered to be testes and the two 

 longitudinal canals to be vasa deferentia 3 . 



In the hexapod Insects the parts which prepare the seed are 

 always in pairs. There is found indeed in most Lepidoptera and in 

 certain Coleoptera (ex. gr. in Ophonns and Harpalus, genera of the 

 family of the Carabici) a single testis*, but since two efferent canals 

 arise from its lower edge, it is obviously formed by the union of two 



appendages had been confounded together as secreting organs, Ann. desSc. not. II. 1824, 

 p. 281. We owe to C. TH. VON SIEBOLD the most complete investigation of this 

 subject ; see his Fernere Beobachtungen iiber die Spermatozoa der wirbettosen Thiere, in 

 MUELLER'S Archiv. 1837, s. 392 433. If, as VON SIEBOLD assures us, the vesicula 

 copulatrix only seldom contains Spermatozoa, and then usually dead ones, it is less to 

 be wondered at that the experiments of MALPIGHI failed than that those of HUNTER 

 succeeded; they ought to be repeated with better success with the fluid from the 

 receptaculum seminis. LEON DUFOUR still persists in considering all these appendages 

 as ylandes sebifiques. 



1 S. KUTORGA, Scolopendrce morsitanlis Anatome, Petropoli, 1834, 4to. pp. 10, n, 

 Tab. n. figs. 3 5 ; EYMER JONES in TODD'S Cyclop, n. p. 413, fig. 201. 



2 LON DUFOUR, who has given a description and figure of these parts, considers 

 the first pair of these vesicular expansions as testes; the tortuous canals as vesiculce 

 seminales, Ann. des Sc. nat. II. 1824, p. 97, PI. v. fig. 3. 



3 See figures in TODD'S Cyclopced. in. p. 551, (article Myriapoda, by RYMER 

 JONES) and by STEIN in MUELLER'S Archiv. 1842, Taf. xm. figs. 17, 18. 



4 L&)N DUFOUR, Ann. des Sc. nat. vi. p. 133, Tab. vi. fig. 8 of JIarpalus rvfcwnis 

 (copied in WAGNER'S Icon. Pnysiol. Tab. xix. fig. 8). 



