1905.] NATURAL SCIENCES OF PHILADELPHIA. 393 



copulatory setse and none in any way much modified or enlarged. 

 Throughout the entire length they have essentially the form shown in 

 figs. 19 and 20, the ventral ones averaging somewhat longer and stouter. 

 The two divisions of the tip are nearly equal in length, especially in 

 posterior setee, but the distal is usually longer and the proximal stouter. 

 The simple digestive tract has the pharyngeal diverticulum divided 

 into two lobes by a median fissure in II and III ; the chlorogogue in- 

 vestment begins in V or even IV, and the posterior region of the intes- 

 tine is very strongly beaded. The anterior margin of the brain, near 

 which the connectives arise, is nearly truncate, but has two pairs of 

 small ganglionic projections; the posterior is about one-half as wide 

 and produced into a pair of prominent lobes separated by a narrow 

 sinus, through which the dorsal vessel passes. Nephridia are of the 

 usual type, symmetrical, and open immediately in front of the ventral 

 setae. 



The chief characteristic of the species is found in the reproductive 

 organs, especially in the abruptly bent atrium. The testes are in X, 

 the ovaries in XI, the latter filling a large part of the cavity of that 

 somite, but apparently unprovided with an ovisac. The former pro- 

 duce spermatogonia very copiously and fill not only the cavity of X, 

 but a prominent median sperm sac which reaches to about XXI. The 

 male genital ducts (fig. 21) present the structure and complexity of 

 Eisen's genus Camptodrilus. The large discoid sperm funnel is in con- 

 tact with anterior face of the septum ^j, on the posterior side of which 

 the vas deferens has contracted to a diameter of one-eighth to one-tenth 

 its diameter. From this point the vas deferens forms many and varied 

 coils and loops (not accurately represented in the figure) and has a total 

 length to the point of entrance into the sperm reservoir of about three 

 and one-half times the entire atrium. The sperm reservoir (ss.) is 

 stoutly fusiform, constitutes nearly one-fourth of the entire length of 

 the atrium and receives the massive prostate gland (p.) near the middle 

 of the ventral side. A ductus ejaculatorius about as long as and one- 

 fourth to one-fifth the diameter of the reservoir unites the latter with 

 the penis sac. Sometimes this ductus is folded as in the figure, and has 

 a posterior connection with the sperm reservoir ; in other examples it 

 stretches forward beside the penis sac, and the ends of the reservoir are 

 reversed. The penial apparatus is bent sharply at the summit of the 

 bursa at nearly a right angle and extends thence caudad, sometimes 

 horizontally, sometimes obliquely upward, carrying with it the septum 

 ?jj to a point opposite the setse zone of XII. The penis is the direct 

 continuation of the vas deferens, and is slightly bulbous at the distal 



