The Anatomy of Chlamydoselachus 445 



quite immature specimen. No. IV, has a total length of 1398 mm. It is evident that, 

 allowing for individual variations, the female Chlaynydoselachus reaches almost or quite 

 full siz;e before attaining sexual maturity. 



The Ovaries. — In Chlamydoselachus, the ovaries (Text-figures 85 to 88) are a pair 

 of elongate, more or less flattened organs situated in the anterior part of the body cavity 

 and attached, rather indirectly, to the dorsal body wall by means of broad mesenteries. 

 In specimens I and II, throughout their entire length the ovaries are attached by their 

 special mesenteries (mesovaria) to the ventrolateral surfaces of the oviducts including the 

 shell glands. In my immature specimen. No. IV, the ovarian mesenteries are attached 

 to the median dorsal mesentery just ventral to the attachments of the oviducts. In 

 No. Ill the ovarian mesenteries are attached as in No. IV, save that where these mesen- 

 teries pass along the ventral surfaces of the shell glands they are fused to the latter 

 organs. In Text-figures 85 to 88 the ovaries are displaced laterally as far as their attach' 

 ments allow. 



In specimen No. IV the two ovaries (Text'figure 85) are much alike. The length of 

 each ovary is about 180 mm., the maximum width (near the anterior end) is 20 mm., and 

 the maximum thickness is 6 mm. The largest follicles, which are in a collapsed and 

 flattened condition, measure only 10 mm. in their greater diameter. Since the mature egg 

 may be 100 mm. long and 60 mm. wide — measurements based on Nishikawa's (1898) Fig. 

 1, pi. IV — it is evident that, in the ovaries under consideration, the ovocytes are very 

 incompletely developed. There are no ruptured foUicles indicating that ova have been 

 liberated. Only the largest follicles are represented on the ventral surface. The dorsal 

 surface shows, in addition to the large follicles, many smaller ones. 



In specimen No. Ill the ovaries (Text-figure 86) are of almost equal si2;e but the 

 left is slightly better developed. In each ovary, the largest follicles are situated along the 

 lateral margin. Since the largest folHcle has a diameter of only 17 mm., it is evident that 

 the ovocytes are decidedly immature. 



In specimen No. I the posterior part of the right ovary (Text-figure 87) is missing, 

 and has apparently been cut away. From the shape of the remaining portion, I infer that 

 this ovary was originally much larger than the left one which is intact. No follicles are 

 represented on the ventral surface of either ovary, but on the dorsal side of the left 

 ovary some small follicles, none more than 2 or 3 mm. in diameter, were found. 



In specimen No. II the posterior part of the right ovary (Text-figure 88) is missing. 

 The preservation of this organ is very poor, so that it is difficult to distinguish a cut edge 

 from a mutilation produced by handHng. Doubtless the rupture of large foUicles has 

 played a part in the disintegration or contraction of this ovary. No follicles are recog- 

 nizable from the ventral surface. On the dorsal surface are protuberances due to the 

 presence of many small follicles, none exceeding 4 mm. in diameter; there is also a con- 

 cavity, 15 mm. in diameter, which represents the persisting half of a follicle. It is not 

 likely that this folHcle has ruptured naturally. In the left ovary no follicles are recog- 



