116 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 
Station 5494 (lat. 9°06’ N., 125°19’ E.); 1,241 meters; August 2, 
1909. One fairly complete specimen, 82 mm. long. 
Station 5511 (lat. 8°15’ N., long. 123°57’ E.) ; 750 meters; August 
7,1909. Fragments of two young specimens. 
Station 5512 (lat. 8°16’ N., long. 123°58’ E.) ; 814 meters; August 
7.1909. One specimen 95 mm. long, oral side lacking, and fragments 
of two smaller specimens. 
Station 5528 (lat. 9°25’ N., long. 123°39’ E.) ; 803 meters; August 
11, 1909. Two large specimens, plastron lacking, and one smaller, 
almost complete specimen. 
There are also a couple of fragments of a large specimen, without 
label. 
Remarks.—The two larger specimens from station 5528 are 135 mm. 
long, 114 mm. broad, and 60 mm. high; the smaller specimen is 80 mm. 
long, 67 mm. broad, and 27 mm. high. The young specimen from sta- 
tion 5491 is 40 mm. long, 32 mm. broad, and 13 mm. high; this is the 
smallest specimen known of this species. Genital pores do not ap- 
pear until a length of about 80 mm. is reached; this is in good ac- 
cordance with the large size to which this species grows. The test of 
the young specimens is, on the whole, low, not at all conical or sub- 
conical, as is the case in the adult specimens, and recalls to no small 
degree Argopatagus vitreus, from which it is, however, at once dis- 
tinguished by its well-developed petals and by the conspicuous notch in 
the front end of the test, as well as by the presence of a peripetalous 
(or marginal) and a subanal fasciole. It is particularly important 
that there is a well-developed subanal fasciole in these young speci- 
mens; also one of the large specimens has a well-developed subanal 
fasciole, whereas the other one has only an incomplete subanal fasicole, 
only the anterior part of it being present. The presence of the subanal 
fasciole in this specimens proves that Koehler (op. cit.) was right 
in referring this species to the genus Linopneustes. 
The pedicellariae were very carefully described and figured by 
Koehler (op. c7t.). The two large specimens from station 5528 are in 
a very poor state of preservation and show only a very few of the 
slender form of tridentate pedicellariae; in the small specimens 
pedicellariae are fairly numerous; some of the tridentate pedicellariae 
have four valves. Only a single example of the characteristic coarse 
form of tridentate pedicellariae (cf. Koehler, op. cit., pl. 17, figs. 42, 
45, 46, 49) was observed. Of considerable interest is the fact that 
ophicephalous pedicellariae are found on the oral side of the young 
specimens, in the posterior part of the posterior ambulacra. The 
values are constricted in the middle, thus very different from the pe- 
culiar ophicephalous pedicellariae of Argopatagus. Even a sort of 
globiferous pedicellariae, with remarkably irregular valves, occurs— 
but very rarely—in the young specimens. 
