488 



TEXT-BOOK OF ENTOMOLOGY 



part of the external genital armature. The so-called penis is long, 

 slender, and dilated at the end, but is not perforated. 



In the locusts (Acrydiidae) the testes are, unlike those of most 

 other Orthoptera, closely united to each other so as to form a single 

 mass of tubular glands into which penetrate both simple and dilated 

 tracheae; the entire mass is situated in the 3d, 4th, and 5th 



abdominal segments, 

 and above the intes- 

 tine. The anterior 

 end of the testicular 

 mass is rounded and 

 held in place by a 

 broad, thin band, one 

 on each side ; two 

 similar bands are 

 situated a little be- 

 hind the middle of 

 the mass. From the 

 under side, and a 

 little in advance of 

 the middle of the 

 mass, two straight 

 small ducts, as long 

 as the testicular mass, 

 pass obliquely to the 

 sides of the body, 

 at the posterior end 

 of the 7th segment of 

 the abdomen ; these 

 are the vasa defer- 

 entia. Each vas de- 



FIG. 461. A, male organs of the cockroach, ventral view: 

 Ts, testis; VD, vas deferens; DE, ductus ejaculatorius ; U, 

 utriculi majores ; , utriculi breviores ; 2, dorsal view ; 3, CG, 

 conglobate gland and its duct. B, male organs, side view : A, titil- 

 lator ; B, penis ; other letters as in A. After Miall and Denny. 



ferens, with its mate, 

 forms a convoluted 

 mass of tubes, com- 

 prising twenty folded 

 bundles (epididymis of Dufour), and two single, long, convoluted 

 tubes, the vesiculce seminales, which are lobed in the 6th and 7th 

 segments of the abdomen. The two vesiculae unite over the 5th 

 abdominal ganglion, forming a thick, very short canal (ductus 

 ejaculatorius), which passes into a large spherical muscular mass 

 (praeputium), behind which is the large intromittent organ (penis), 

 which forms a short chitinous cylinder, quite complicated in struct- 



