808 PROCEEDINGS OF THE ACADEMY OF [DcC, 



female pores are situated close together between the ventral setae of 

 XIV, but a-c invisible in surface views. 



*- No complete coelomic septa exist anterior to ^j , this space being 

 largely occupied by the radiating pharyngeal muscles; ~^^ is slightly 

 thickened, y^^ and ^jj about twice as thick, and ^j^^j to -Jj each about 

 fom- times as thick as ordinary septa and extremely muscular. From 



VT VIII 



vn *^ IX" *^^^ septa are strongly funnel-shaped and "nested." The 

 pharynx occupies III and IV, a short oesophagus X, the strongly mus- 

 cular gizzards VI and VII ; then follows a straight narrow canal which 

 appears to lack calciferous pouches, but is slightly enlarged with yel- 

 lowish, thickened and very vascular walls in the posterior part of X 

 and presents a similar' but less pronounced structure in XI. The true 

 sacculated intestine begins in XVIII. The anus is a wide vertical 

 slit. The brain is transverse, about five times as wide as long, without 

 median constriction or any lobing, and is situated in II. The ventral 

 cord is remarkable for the complete and extremely thick muscular 

 sheath, which equals h the diameter of the cord proper at a ganglionic 

 enlargement. Although present in other species of Diplocardia, the 

 muscular sheath is in this one thicker than usual. Apparently there 

 are no peculiarities of the vascular system. Unlike the type species 

 the dorsal vessel is single and undivided throughout in the three exam- 

 ples dissected. Strongly enlarged hearts occur in XIII, and a slightly 

 enlarged pair in XII. The nephridia begin in III, and appear to be 

 present in every succeeding somite. Except for the first five pairs, 

 which are more compactly coiled and of smaller size, they have the 

 long-looped form described for other species of the genus. 



Three pairs of spermathecse exist in the anterior parts of somites 

 VII, VIII and IX, attached to th? body floor at the base of the corre- 

 sponding septa, behind which they rise freely to a high level, though 

 occasionally they pass through the neural arch of the 

 septum nto the preceding somite. All of the sperma- 

 thecse have the pouch and stalk very distinctly differ- 

 entiated and 'are especially characterized by the great 

 length of the latter and the very low position of the 

 diverticulum which arises from its lateral s'de at the 

 point at which it enters the body wall. The pouch 

 has in general the form shown in fig. 1, which represents 

 the second spermatheca, and in all of the specimens 

 examined is strongly flattened latera ly. The stalk is 

 Fio-. 1 ^ ^^ \esLSt as long as and usually longer than the pouch, 

 £.nd also more or ?ess flattened by the pressure of the 



