80 BULLETIN OF THE 



they resemble to sucb an extent the genus Pygaster that they may be after all the 

 young of the species of Pygaster uieutioned by Loven as found in the West 

 Indies. A very critical revision of the young of Echinolampas and of Conocly- 

 pus is necessary to define the systematic position of these young sea-urchins. 



Station 155. 88 fathoms. Off Montserrat. 



" 177. 118 " " Domiuica. 



" 220. 116 " " St. Lucia. 



" 272. 76 " " Barbados. 



Poxirtalesia miranda A. Ag. 



Fragments of some of the other genera of Pourtalesise but too imperfect for 

 accurate determination, were also collected, principally from Barbados. 



Station 265. 576 fathoms. Olf Grenada. 



Urechinus naresianus A. Ag. 



This is another of the abyssal species having a most extensive geographical 

 range. I am unable to distinguish the specimens collected by the "Blake " from 

 those collected by the " Challenger " in the Southern Ocean. 



Station 222. 422 fathoms. Off St. Lucia. 



" 308. 1242 " Lat. 41° 24' 45" N., Long. 65° 35' 30" W. 



Homolampas fragilis A. Ag. 

 Station 162. 734 fathoms. Off Guadeloupe. 



Palaeotropus Thomsoni A. Ag. n. sp. 



At Station 781 a single broken specimen of this species was collected, it differs 

 most strikingly from all the other specimens of Pala?otropus collected. It is 

 closely covered by uniform tubercles on the abactinal side. It has a proportion- 

 ally greater number of coronal plates, and a high test, with a keeled posterior 

 interambulacral median line. Apex more posterior than in P. Josephina. 



The color of tlie test is yellowish Avliite wlien alive. Tiie large P. Josephina- 

 are of a dirty greenisli red color, and when young more piakisli. This species is 

 also remarkable for its broad, bare posterior lateral ambulacra on the abactinal 

 side, and for its prominent keeled, very elongate actinal plastron, and its longi- 

 tudinally elongate anal fasciole, still very prominent at a time when in P. Josephina 

 the posterior extremity has become flattened, and the fasciole quite indistinct. 



Station 321. 233 fatlioms. Lat. 32° 43' 25" N., Long. 77° 20' 30" W. 



