1872.] e Porcupine ' Dredging -Exp editions. 495 



Tooeopneustes, Agassiz. 



1. T. drobachiensis, Miiller. 



Of this species it seems to me that T. pictus, Norman, and T.pallidus, 

 G. O. Sars, can only be regarded as varieties. It is generally distributed 

 at depths beyond 100 fathoms. 



2. T. brevispinosus, Risso, sp. 

 Shallow water on the coast of Spain. 



Psammechinus, Agassiz. 



1. P. miliaris, Lam., sp* 



2. P. microtuberculatus, Ag. 



Cassidulidjs. 

 Neolampas, A. Agassiz. 

 This genus, with a nearly central pentagonal mouth and a tolerably 

 distinct iloscelle, with the anal opening at the bottom of a deep posterior 

 groove excavated in a kind of projecting rostellum, with narrow ambulacral 

 arese and a small compact group of apical plates, must be referred to the 

 Cassidulidse ; but it differs from all known genera of the family, living or 

 extinct, in having no trace of a petaloid arrangement of the ambulacra, 

 which are reduced on the apical surface of the test to a single pore pene- 

 trating each ambulacral plate, and thus forming a double row of alternating 

 simple pores for each ambulacral area. 



1. N. rostellatuSy A. Ag. 



I believe I am correct in referring to this species a single specimen 

 dredged at the mouth of the English Channel. It is upwards of an inch 

 in length, and therefore nearly double the size of the examples procured 

 by Count Pourtales in depths from 100 to 150 fathoms in the Strait of 

 Florida. 



Clype astride. 

 Echinocyamus, Van Phelsum. 

 1. E. angulatusy Leske. 



Generally distributed, but not found living beyond 150 fathoms. 



Ananchytid^e. 

 Pourtalesia, A. Agassiz. 

 According to the classification of Desor, which makes the "disjunct " 

 arrangement of the ambulacra at the apex the test character of the Dysas- 

 teridse, this genus should be referred to that group ; for the apical disk is 

 truly decomposed as in Disaster and Collyrites, and not merely drawn out 

 as in Ananchytes. From the arrangement and form of the pore-plates, 

 however, and from the general appearance and habit of the animal, I am 

 inclined to think with A. Agassiz that its affinities are more with such 

 forms as Infulaster. Pourtalesia must be an aberrant form, in whatever 



