16 BULLETIN 84, UNITED STATES NATIONAL MUSEUM. 



show out of the mouth shields a few small distal plates. The under brachial 

 plates are less developed in the new species and they become a little longer than 

 wide only between the fourth and the seventh article or thereabout, after which 

 they rapidly become very small and triangular; I notice, on the contrary, that in 

 0. convexa these plates remain longer than wide on the longest part of the arms, 

 and they do not assume a triangular shape until near the last articles. All these 

 differences may readily be understood from the photographs which I reproduce here 

 (pi. 2, figs. 3-6). It will be seen that a specific separation is amply justified. 



Let it be added, also, as Lyman stated, that 0. convexa has always been caught 

 in great depths, while the specimens of the Blake came from depths ranging between 

 114 and 270 fathoms; the two specimens of the Albatross were found somewhat 

 deeper. 



One might also compare 0. coronata with 0. solida Lyman, in which the plates 

 of the upper face of the disk are arranged in a similar manner, but the characters 

 of the under face, and among others the shape of the mouth shields, which are very 

 small, as well as that of the under brachial plates, make any comparison impossible. 



OPHIOGLYPHA ELEVATA Lyman. 

 Plate 3, fig. 5. 



Ophioglypha ekvata LYMAN (78), p. 82, pi. 4, figs. 87-89. 

 Ophioglypha elevata LYMAN (82), p. 57, pi. 5, figs. 16-18. 



Albatross station 2675. Lat. 32 32' 30" N.; long. 77 15' W.; 327 fathoms; 

 gy. s. bk. sp. sh.; temp. 45.8 F. One specimen. 



The diameter of the disk is 7 mm. ; none of the arms is preserved to its entire 

 length. 



Lyman's type was found by the Challenger in lat. 46 40' S. and long 37 50' 

 E., in a depth of 310 fathoms. Notwithstanding the long distance between the 

 stations, the example found by the Albatross really belongs to Lyman's species, 

 although I notice a few differences which are rather unimportant and are undoubt- 

 edly due to the fact that the type was a little smaller, the diameter of the disk not 

 exceeding 6 mm. 



Lyman says that the tentacular oral pores offer two scales on each side; in 

 my specimen I observe three on the interradial side and two or three on the radial 

 side. The following pores have three and sometimes four scales on the proximal 

 and external side. This number then falls to two and remains so on the whole 

 preserved length of the arms, while the distal and internal side generally con- 

 tinues to show three papillae. These papillae are not so sharply limited as the 

 external scales, but they are, nevertheless, plainly noticeable; at a certain distance 

 from the arm base the number of these scales falls to two, and finally to one. 

 The mouth shields are wider distally than indicated in Lyman's drawing in the 

 "Reports of the Challenger" (82, pi. 5, fig. 16); in the drawing in the Bulletin 

 (78, pi. 4, fig. 87), the distal region is represented wider, but with fairly sharp 

 lateral angles, while these are actually rounded. 



The first under brachial plates of 0. elevata are known to carry in their middle 

 a longitudinal swelling which is characteristic of the species. Lyman says that 

 this swelling is within the disk and he represents it on the first four ventral plates. 

 In my specimen this swelling appears on the first five plates at least. On the first 



