174 Natural History Bulletin. 



that it was not an animal to be handled with impunity, as its 

 spines, although small, were exceedingly sharp, and inflicted a 

 wound so painful as to suggest some poisonous properties. 

 The specimen was of a dull vinaceous color. 



A few specimens of Echinonietra snbaiig'iilan's Desml. were 

 found in comparatively shallow water. Two representatives 

 of the sculptured sea-urchins such as flourished during tertiary 

 times were secured. One was Te}niicc/ii>iiis inantlatiis A. Ag., 

 characterized by a single large anal plate and radiate excava- 

 tions around the primaiy tubercles, and the other. Trigono- 

 cidaris albida A. Ag., having four large, unequal anal plates 

 and the test beautifully ornamented with radiating ridges as if 

 a thread had been wound around and around the test between 

 the spines. The pedicellaria; are more conspicuous than in 

 most species, and the buccal membrane is set with large, ap- 

 parently imbricating plates. Both of these sculptured species 

 are very small in comparison with the others collected by us, 

 and are light colored, the former being light green and the 

 latter a buffy white. Thev are abundant on the Pourtales 

 Plateau from eii^htv to two hundred and flftv fathoms. Echi- 

 iius gTacilis A. Ag. is another abundant species, which is 

 much more conspicuous than the last, being brightiv colored 

 and the largest species from this region excepting Asthenosoma 

 hystrix. It is almost globular in form, and the test is a vivid 

 green with vertical series of sharply defnied, diamond-shaped 

 white markings. The spines are white, short, and somewhat 

 sparse. Next to Dorocidan's ^apillata, this was the most 

 abundant species of sea-urchin found on the plateau. 



Onl^' two species of Clypeastrids were collected here. 

 Clypeasfer stthdcprcssus Ag. is a flat species with the centro- 

 dorsal region somewhat abruptly raised into a dome-shaped 

 ■eminence. This species is particularh' interesting from its 

 unusual distribution, being found on the African coast and off 

 the coast of Florida. I have not heard of its occurrence be- 

 tween these widely separated localities. It was dredged from 

 a depth of about sixty fathoms. Pahcotroptis josephciue Loren 

 is the only representative of the Petalosticha that we secured. 



