41 
u'oodi, Fbs., whereas the normally suhconical individuals of 
that species do not possess these structures; the latter were 
therefore separated hy Professor Forbes as Teninechinus melocactus. 
M. de Loriol has figured a specimen of Tripneustes variegatus, 
from Mauritius, which has a very similar series of cavities, and 
it is interesting to note that it is here also accompanied by a 
marked depression in form. I am indebted to Prof. F. Jeffrey Bell 
for showing me a series of specimens of the same species from 
Mauritius, in which the same structures occur, though they are 
often very irregular. The majority of the specimens of the 
recent species are normal, whereas in Teninechinus it is the 
reverse. Until a dissection of one of the Mauritius specimens 
has been made, it is very hazardous to express any opinion upon 
the matter, but the striking regularity of these depressions, 
especially in Teninechinus woodi suggests that they are not mere 
malformations. It may be that they are marsupial pouches as 
suggested also for T. ivoodi, analogous to the deeply impressed 
ambulacra in some Spatangoides, as Hemiaster cavernosus 
(Phil.); and if so, the conical forms without these cavities may 
be the males. 
Echinus sphaeroideus, (Cotteau) 1880. PI. I., fig. 5 & 6, 
Coralline Crag. Boyton. 
There is a beautiful little specimen of this species in the 
collection ; it agrees fully with M. Cotteau’s admirable figures 
and descriptions. It has not been previously recorded as 
occurring in England. 
Family ECHINOMETEID^. 
Genus Strong ijlocent rot us. Brandt, 1834. 
Strongylocentrotus scabe)\ n. sp. PI. I., fig. 7. 
Form :—-Low and depressed abactinally: well rounded 
at ambitus. 
Apical system, large. 
Ambulacra :—The pores are in arcs of six pairs: near the 
summit they form a nearly vertical series, but at the ambitus 
they are in oblique curves. There are eight or nine plates 
between the summit and the ambitus. The tubercles are large 
though smaller than in the interradii. 
