Mr. W. T. Blanford on Fairbankia bombayana. 399 
belonged to the same Petaloproctus. Perhaps Rhodine Lovent, 
Malmer., also belongs here. 
Malmgren follows the Maldaniea with the Ammocharidea 
as a distinct family, founded upon the genus Ammochares. 
He also describes a second genus, Myriochele, which seems 
almost to coincide with Psammocollus, Gr., but gives no cha- 
racter of the family, at least in his most recent work (‘ An- 
nulata polycheta Spitzbergie’ &c.). Kinberg, who esta- 
blishes the same family, finds its character in the tentaculiform 
branchiz seated on the buccal segment, in a change of bristles, 
and in the presence of superior setee, and very numerous and 
minute uncini placed below them. The author would indi- 
cate (at the same time bringing together Ammochares and 
Psammocollus) that the body consists of only a few segments, 
increasing considerably in length towards the middle, that 
these are all furnished with sete, and, with the exception of 
the foremost and hindmost, also with uncini (which, however, 
are placed in more than double and irregular rows, and not 
upon cushions), and that the buccal and terminal segments 
bear no plates, although the buccal segment may be produced 
in front into a lobe (cephalic lobe?) slit up into branches at 
the anterior margin. Their similarity to the Maldaniea, 
already treated of, strikes one at once; but with this concep- 
tion of the character, Kinberg’s genus Sandanis, as to the 
position of which he seems to be still doubtful, cannot be 
added to them; it should not be separated from Capitella. 
To Ammochares belong 4 species:—A. ottonis, Gr., A. 
assimilis, Sars, A. tegula, Kinb., and A. Sundevalli, Kinb., 
the last known only by its anterior part. 
Of Psammocollus we know only one species, P. australis, 
Gr., from the island of St. Paul; and of Myriochele likewise 
only one, Myriochele Heert, Malmgr., which has been ob- 
served, but not abundantly, at Spitzbergen and Greenland. 
XLIX.—Deseription of Fairbankia bombayana, a new Genus 
and Species of Rissoidee from Western India. By WILLIAM 
T. BuanrorD, A.R.S.M., F.G.S., C.M.Z.S. 
THE shell described below is one of the numerous peculiar 
estuarine forms so common on the shores of tropical seas. I 
have found but few specimens myself, and am indebted for a 
much larger number to the Rev. 8. Fairbank and Dr. Leith. 
The latter very kindly procured me some living specimens 
about five years since. I had for a long time supposed the 
species to be a Rissoa; but two years ago I had occasion to 
