ECHINOIDEA. II. i^g 



when I x'eiiture to suppose tliat Br. lyrifcra is not at all found on the American side of the Atlantic. 

 In any case it cannot be taken as proved by any of the statements hitherto made of its occur- 

 rence there. 



From the U. S. National Museum I have received a specimen of Brtssopsis lyrifera^> from 

 «Albatross> St. 2401 1142 fathoms; Gulf of Mexico. Rathbuu 336. p. 616), which is evidently identical 

 with the iglobular typo figured by Agassi z in Blake -Ech. PL XX\'I. Fig.s. 13 — 18. vSpecimens of 

 the same form I have further seen in the U. S. National Museum, the IMuseum of Yale College and 

 in the British Museum from the «Albatross> St. 2400 and 2401 and from the Blake St. 49. From the 

 latter station there are three specimens of this form in the British Museum wrongly identified as 

 Periaster liniicola A. Ag. — A close examination of this form shows that it is not Fir. lyrifcra., but a 

 very distinct species, which I shall describe here under the name of Brissopsis alta n. sp. 



The shape of the test (PI. III. Figs. 5, 8, 9, 13, 16) is distinctly higher and more globular' than 

 in lyrifcra. as is also well seen in the figures in the v:Blake»-Echinoidea quoted above. The actino- 

 stonie is \-ery near the anterior end ,of the test, distinctly more so than in lyrifcra. The labrum is 

 prominent, with a rather broad posterior prolongation, not reaching the second adjoining ambulacral 

 plates. The first ambulacral plate reaching within the subanal fasciole is the 6th; three pairs of pores 

 are enclosed within the fasciole. No anal branches of the fasciole are developed. The rather small 

 anal area is placed near the upper side on the high, beautifully arched posterior end. The petals are 

 short and rather broad, the posterior about two thirds as long as the anterior ones; in larger sjoeci- 

 mens they are rather deepened. The posterior petals are completely separated, though scarcely so 

 widely as is generally the case in lyrifcra; the tubercles appear already- on the second — third plate of 

 the posterior interambulacnmi (as in lyrifcra), and only the three inner pores of the inner series of the 

 posterior petals are rudimentary. The area enclosed by the peripetalous fasciole is somewhat smaller 

 than in lyrifcra ; it is rather broad, not much narrowed in the posterior lateral interambulacra, produced 

 somewhat backwards in the odd posterior interambulacrum. The odd anterior ambulacrum is only 

 slightly sunken, the front end of the test being almost regularly rounded, especially in the smaller 

 specimens. In the specimen received from tlie U. S. National Museum there are only three genital 

 pores, which is, however, evidently an abnormal case, all other specimens seen by me having four 

 genital pores. — The tubefeet and their spicules are as in lyrifcra, the spicules only may be a little 

 more thorny. Some of the rosette-plates may be coalesced. 



The pedicellarise give very good characters distinguishing this species from lyrifcra. The glo- 

 biferous pedicellarise (PI. XVIII. Figs. 27, 29) have the terminal opening of the valves surrounded by 

 6 or 8 short teeth; the blade is a quite closed tube, somewhat curved. The basal part has a rather 

 close meshwork at the bottom; the edges are smooth as is also the apophysis. The valves are as in lyri- 

 fcra enclosed by a thick skin, probably glandular, but without glandular sack. There is no neck. The 

 stalk is provided with an irregular, sometimes very large limb with numerous free, upwards directed 



• In the Blakes-Echinoidea (p. 701 Agassiz sets forth the opinion that the .globular test . is an jembrj'ouic feature^. 

 I cannot see the reason for regarding this shape of the test as more embr\'onic than the oval, elongate form. If it be proved 

 that a species like the Br. elotigata described below is globular in its 3'oung stages, there may be some reason for seeing a 

 more primitive' feature therein. But, as far as my experience goes, it cannot be said to be a general character of young 

 Spatangoids that their test is comparatively more globular than the test of the grown specimens. 



