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was now proved to be the true one ; they were further shown to 
constitute a distinct family— the Hippuritidai, and to furnish the only 
instance of a whole family of bivalve shells which has become extinct. 
He subsequently described a new and remarkable genus of 
Ilippurites from Jamaica, which he named Barrcttia, in honour of 
the late Lucas Larrctt. 
Another obscure form which he investigated, was a new and 
anomalous Echinoderm from the Chalk of Kent, and he named it 
Echinothuria floris, after the discoverer, Mr. J. Wickham Flower. 
Its particular rank and affinities were not apparent j but in 
describing it the author said, “ the publication of it should be 
acceptable to those who base their hopes on the ‘ imperfection of 
the geological record,’ as it seems to indicate the former existence 
of a family or tribe of creatures whose full history must ever 
remain unknown.” 
It is most interesting to find that these anticipations have been 
strangely set at naught, for Sir C. Wyville Thomson, in his 
‘ Depths of the Sea,’ has actually founded the family of Ecliino- 
thundcc, to contain, besides the original fossil named by my father, 
two recent genera, Calverki and Pltormosoma, which have been 
brought to light by the recent deep-sea dredgings. And ho 
lemaiks that Woodward “describes the Chalk species E, fioris, 
almost as fully and accurately as we could describe it noAv with a 
full knowledge of its relations.”* 
In 1856 ho identified a number of land and freshwater shells 
from Kashmir and Tibet, and observed it was “somewhat surprising 
to find, that of 22 sorts collected by Dr. Thomson, one half were 
Lritish species, and the rest of the commonest and most widely 
diffused Indian forms.” He also described four new species of 
freshwater shells from Lake Tanganyika in Central Africa, collected 
by Captain Speke. 
The genus Synapta — a marine aniinal allied to the Sea-cucumbers 
— formed the subject of a paper by Lucas Barrett and himself. 
The species (of which one new one was described) are familiar to 
all workers at the microscope, comprising spicules which present 
the appearance of miniature anchors. 
* See ‘Depths of the Sea’ (1873), pp. 163, 164 ; also paper by R. Etheridge, 
Jun., Quart. Journ. Qeol. Soc. vol. x.xx. p. 307. 
