CHITON. 
Puate X. 
Species 53. (Mus. Cuming.) 
CHITON FASCICULARIS. Chit. test@ oblongo-ovatd, valvis 
summitate levibus, postice subrostratis, utringue cre- 
berrimé minute granulatis ; cinereo-luted, interdum 
strigis undulatis fuscis concentricé pictd, summitate 
interdum nigra; Vigamento setoso, spicularum cristis 
ornato. 
THE FASCICLED Curton. Shell oblong-ovate, valves 
smooth along the summit, somewhat beaked poste- 
riorly, very closely minutely granulated on each side ; 
ashy yellow, sometimes concentrically painted with 
waved brown streaks, summit sometimes black; lig- 
ament bristly, ornamented with tufts of spicule. 
Linnzus, Syst. Nat. (12th. edit.) p. 1106; (not of 
Chemnitz). 
Chiton crinitus, Sowerby (not of Pennant). 
Hab. Mediterranean and Channel Islands. 
Naturalists are still somewhat divided in opinion as to 
whether the fasciculate Chitons of the seas of Europe are 
modifications of one and the same species, or whether they 
constitute two specifically distinct from each other. That 
Lamarck should have recorded them under one, after the 
manner of Linnzus, is not to be wondered at, considering 
his very limited knowledge of the genus; Philippi de- 
scribes but one, very significantly adding “‘varietates vel 
potius species due occurrent”, and details the characters 
of each precisely as I have observed them. Mr. Sowerby 
considers them as distinct species; he assigns the smaller, 
which is found the more abundantly on our own coast, and 
of which the granules are the larger, to the C. fascicularis 
of Linnzus, and that under consideration, chiefly inhabit- 
ing the Mediterranean and English Channel, to the C. cri- 
nitus of Pennant, 
After a careful investigation of the subject I am led to 
conclude, with Mr. Sowerby, that the C. fascicularis and cri- 
nitus are distinct species, but I think he has erred in his 
- identification of names. The larger species above de- 
scribed, inhabiting the Mediterranean and English Channel, 
and in England only the south coast, appears to be the 
original C. fascicularis of Linneus, “from the coast of 
Barbary ”, whilst the smaller, which inhabits our coasts 
throughout and as far north as the Shetland Islands, is 
the C. crinitus, figured on an enlarged scale by Pennant. 
The C. fascicularis of Chemnitz which Mr. Sowerby con- 
siders “beyond doubt ” identical with the Linnean species, 
answers to neither of those in question; it refers rather to 
the C. Zelandicus of Quoy, represented in the following 
plate at Fig. 58, which may be regarded as the tropical 
analogue of our British C. crinitus. 
The @. fascicularis is sometimes very prettily variegated 
with concentrice zigzag painting, sometimes pale, black 
and shining along the summit, and the surface is invariably 
more finely granulated than in the smaller C. crinitus. 
Species 54. (Mus. Cuming.) 
CHITON HIRUDINIFOMIS. Chit. testd subelongatd, valvis 
medio levibus, subrostratis, utringue minute et creber- 
rime granulatis ; caruleo-aterrimd ; ligamento lato, 
valvarum latera obducto, dense brevisetoso, spicularum 
cristis parvis ornato. 
THE LEACH-SHAPED CHITON. Shell somewhat elongated, 
valves smooth in the middle, minutely and closely 
granulated on each side; very dark blue-black; 
ligament broad, spread over the sides of the valves, 
very thickly set with short bristles, and ornamented 
with small tufts of spicule. 
SoweErsy, Pro. Zool. Soc. 1832. p. 59. 
Hab. Gallapagos Islands and coast of Peru (under stones 
at low water); Cuming. Korean Archipelago; 
Sir Edward Belcher. 
There is very little variety of sculpture in the fasciculate 
species of Chiton; the present is perhaps most easily dis- 
tinguished by its very dark blue-black colouring. The 
specimens, of which the localities are recorded above, are 
from such very remote parts of the world that I hesitated 
to think they could be of the same species; those from 
the Korean Archipelago, collected by Sir Edward Belcher 
during the voyage of the ‘Samarang’ are broader, stouter, 
and more convex than the Pacific specimens. 
Species 55. (Pl. X and XI. Mus. Brit.) 
CuITON SITKENSIs. 
levibus, clypeiformibus, posticé utringue lobatis, posticd 
terminali ad extremitatem umbonatd, anticé parvé, 
margine incisuris senis subdistantibus notatd ; nived ; 
Chit. testa elongato-oblongd, valvis 
pallio amplo, super testam omnino obducto, spicular 
vitrearum asteriscis minutissimis pulcherrime ef den- 
sissime obsito. 
April, 1847. 
