240 PROCEEDINGS OF TEE NATIONAL MUSEUM. yol. 48. 



No deposits in genital tubes. Calcareous ring is of the common shape, 

 Polian vesicle single. Genital tubes branched many times, forming 

 two tufts, and opening on a papilla; near it also opens the stone-canal. 



This species differs from /. ijimai in, first, the smaller number of 

 dorsal papillae, second, the presence of complicated rosettes, and 

 third, absence of spicules from genital tubes. I. maculatus has the 

 large wheels and complicated rosettes similar to those of the present 

 species, but the dorsal papillae are much more numerous, there being 

 140-150 in each ambulacrum. 



Habitat. — Off Jogashima, Miura Peninsula, Sagami. 



Type.— Cat. No. 34156, U.S.N.M. 



Family ELPIDIID^E TheeL 



Genus PENIAGONE Theel. 



31. PENIAGONE JAPONICA, new species. 

 Plate 9, fig. 10. 



Station 4974. Three specimens. 



Station 5083. One specimen. 



Station 5084. Seven specimens. 

 The anterior end of body is bent ventrad, and in its center opens 

 the mouth. On the dorsal side of the necklike region there is a trans- 

 verse series of four papillae, 10-14 mm. long, connected together at 

 bases by a weblike fold; two more pairs of minute papillae immedi- 

 ately behind. Along each side of body a lateral brim separates the 

 ventral from the dorsal surface. Length of body 55 mm., width about 

 one- third the length. Color pale white all over. Integument thin 

 and soft, slightly rough to the touch. Tentacles large, probably 10; 

 only 6 could be made out owing to bad preservation. About 8 pedi- 

 cels form a single row along each side of the posterior half of body, 

 beneath the lateral brim. The anteriormost ones are largest, meas- 

 uring about 4 mm. in length. Deposits in dorsum are of two kinds, 

 lying in distinct layers. The superficial ones are of the common 

 shape, consisting of a short central rod and 4 bent thorny arms, each 

 with a shorter vertical process near the base. The arms are 120-200/* 

 long, the vertical processes 70-120 /*. The deeper layer consists of 

 scattered, large X-shaped bodies (pi. 9, fig. 10). The arms are 

 straight, bear minute teeth near the free end, and measure 1 40-52 0/i 

 in length, sometimes much shorter, being only 60/(. The central rod 

 is less variable in length, commonly 50/*, but ranging between 40 and 

 80/*. In ventrum, pedicels, and stalks of tentacles are found only 

 those corresponding to the superficial ones of dorsum. The arms are 

 but slightly bent downward, measuring 90-1 40/* long, with vertical 

 processes 20-50/* long. Papillae and tips of tentacles are beset with 



