C. Spence Bate on the Penwidea. 183 
This genus is proposed by M. Alphonse Milne-Edwards 
for those Pencet which do not belong to Solenocera. It is 
founded on a species not yet described that he has seen in the 
collection of the U.S. Mexican-Gulf exploration, but which so 
closely corresponds with Peneus serratus from the Fiji Islands, 
that, if they are not separated by the length of their antennee, 
they appear to be identical; and I have accordingly adopted 
the same specific name. 
Penceopsis serratus, A. Milne-Kidwards, MS. 
Length about 4 inches. 
Taken in the Gulf of Mexico. 
The gradual approximation of the length of the flagella of 
the first pair of antenne, as seen in specimens of Penwus 
caramote on the one hand, where they are so short as to be 
easily overlooked, to that of Pencopsis, where they are half the 
length of the animal, is so gradual that it is difficult, however 
convenient it may be, to determine where the genus can 
naturally be separated; and without any other distinguishing 
feature it can only be accepted as provisional. 
Peneopsis styliferus, Edwards. 
The type of this species appears not to be preserved; or at 
least we could not identify it. M.-HEdwards says that the 
filaments of the first pair of antennee are cylindrical ; it there- 
fore cannot, like the other two species arranged by M.-Kdwards 
in his second division of the genus Penceus, belong to the genus 
Solenocera. : 
Length 4 inches. 
Taken in the neighbourhood of Bombay. 
Penceeus Dobsoni, Miers (Proc. Zool. Soc. March 5, 1878), 
appears to differ from P. styliferus only in the slightly 
different length of the flagella of the first pair of antenne ; 
and, with the exception of the peculiar feature of the fifth 
pair of pereiopoda (which the author considers to be a condition 
of the female, and which appears to be abnormal), I see nothing 
to separate this species from P. styliferus as described by 
Edwards. 
Hab. West coast of India. 
Genus SOLENOCERA, Lucas. 
Milne-Edwards separated the genus Peneus into two 
divisions, the second of which contained “those having the 
terminal flagella of the first pair of antenne longer than the 
carapace,’ and established in it three species—P. membrana- 
ceus, P. crassicornis, and P. styliferus. 
