228 BULLETIN OF THE 



are very rich in species ; such are Ophioglypha, Amphiura, Ophiacantha, 

 and Ophiothrix, which contain two thirds as many species as do all the 

 remaining sixty-eight genera in the family. A peculiar structure does 

 not necessarily entail abundance of species, for the Astrophyton-like 

 Ophiurans (e. g. Ophiomyxa) have few species. 



There are included in this paper three unpublished species from the 

 dredgings of H. B. M. ship " Porcupine," — Ophiockiton tenuisjnnus, 

 Oj'ihiomi/xa serpentaria, and Ophiohyrsa hystricis ; and from the " Chal- 

 lenger " expedition there are one genus and three species whose originals 

 were found among the collections of the late Sir Wyville Thomson. 

 They are Ophiocopa spatula^ Ophiacantha scolopendrica, and Ophiomastus 

 texturati/s. All the rest are from the " Blake " dredgings. 



The following list of species will show all new information as to the 

 depths at which they occur, and. will give some notion of their fre- 

 quency, by the number of stations at which they are found. 



Ophiopeepale Goesiana. Up to 38 fathoms. 



Ophiozona nivea. From twenty-six stations, and in large numbers. Up to 

 50 fathoms. 



Ophiozona tessellata. From seventeen stations. 60-300 fathoms. 



Ophiozona impressa. Down to 300 fathoms. 



Ophiozona antillarum. Ten stations. 94-508 fathoms. 



Ophioglypha Sarsii. Found as far south as 35° 45' 30" N., and down to 306 

 fathoms. 



Ophioglypha lepida. Ten stations. 



Ophioglypha falcifera. Twelve stations. 200-508 fathoms. 



Ophioglypha variabilis. Twenty-six stations. Up to 175 fathoms. 



Ophiomusium eburneum. Twenty-two stations. 95-390 fathoms. 



Ophiomusium Lymani was dredged at only nine stations, but in such 

 quantities that Mr. Agassiz was forced to throw away a large part. These 

 hauls illustrate the abundance of animal life at great depths ; for the shal- 

 lowest station was 810 fathoms. 



Ophiomusium validum. The great number of stations (thirty-two) at which 

 it was dredged show its frequent occurrence, as well as its variation in 

 depth, now known to run from 60 to 1568 fathoms. 



Ophiomusium testudo. Sixteen stations. 69-508 fathoms. 



Ophiomusium planum. Up to 300 fathoms. 



Ophiomusium acuferum. This humble species, described by me in 1875 

 from the " Ilassler " dredgings, proves to be the most widely spread in 

 that fauna. It also inhabits very diverse depths, and must accommodate 

 itself to temperatures varying from 78° to 39° Fah. Strangely enough, it 

 has not yet been found outside the West Indian limits. Thirty-fivo sta- 

 tions. 27-1030 fathoms. 



