1882. } CRUSTACEANS FROM MAURITIUS. 539 
the figure showed distinct differences in the proportions of the 
penultimate joints and dactyli of the chelipedes, and in the coloration 
of the ambulatory legs, and as Milne-Edwards in his later diagnosis 
mentioned the existence of seven series of spines on the carapace, a 
character scarcely applicable to the specimen from the Mauritius, 
and also on account of the widely separated habitats of the two 
forms, I was at first inclined to regard the species as distinct. 
Before, however, applying a new specific name to the specimen from 
the Mauritius, I submitted a sketch of the chelipede and cephalo- 
thorax to Prof. A. Milne-Edwards, who very kindly compared them 
with the type of P. longimanus in the Paris collection, and sent me 
the following observations, with an outline drawing of the Paris 
type :— 
** Le Palinurus longimanus (M.-Edwards) ressemble beaucoup a 
Pespéce qui a été trouvée au voisinage de Vile Maurice et dont vous 
m’envoyez un croquis. Il y a cependant quelques légéres différences 
dans la disposition des épines. Vous pouvez en juger par le dessin 
ou j’ai figuré la carapace du P. longimanus type de notre collection. 
En arriére de |’épine latérale postorbitaire il s’en trouve une seconde 
qui me parait manquer sur l’exemplaire de Maurice. Le doigt 
de la main du Palinurus du Muséum de Paris est moins courbé, mais 
la forme du membre est bien la méme. Ce sont, comme vous 
voyez, de bien petits différences.”’ 
These remarks and the figures so courteously sent leave no doubt 
in my mind as to the specific identity of the two forms. The 
spine behind the lateral postorbital spine, which was not represented 
in the sketch sent to M. Milne-Edwards, is distinctly developed on 
one (the left) side only of the Mauritius specimen, where, however, 
it is very small. 
As no sufficient description or accurate figure has as yet appeared 
of this Palinurus, which is certainly one of the most remarkable de- 
scribed, those which are now given will not be without mterest ; and 
the minor distinctions referred to below will, I think, justify me in 
considering the Mauritius specimen as belonging to a distinct variety 
—the more so as this is, I believe, the first recorded instance of a 
Crustacean from the Mascarene subregion being specifically identical 
with one from the West Indies, unless, indeed, certain species having 
an almost cosmopolitan distribution are to be excepted. This, more- 
over, is in itself a fact of much interest on account of the well-known 
affinities that exist between the Mascarene and South-American 
faunas. 
Whether P. longimanus is to be regarded as an instance of a once 
widely-spread species surviving to the present period in these widely 
distant and isolated localities, or whether further researches will de- 
monstrate its existence at Cape Verd or on the western coast of 
Africa (whence it may have passed round the Cape of Good Hope 
into the Oriental region), time only will show. Certain it is that it 
differs widely from the typical Palinuri in the remarkable develop- 
ment and dilated palms of the anterior legs, which may be taken 
by some zoologists as indicative of an affinity with the Astacina. 
