170° Prof. F. M‘Coy on the Classification of 
fect from the Anomura to the Brachyura. In the general form 
of the carapace, of the rostrum, in the completeness and form of 
the orbits with the two fissures in their upper edge, it so exactly 
resembles Corystes as to have even deceived Dr. Leach, the first 
crustaceologist of his day (see Mantell’s Geol. of Sussex, p. 97). 
I first suspected its anomurous nature from observing the faint 
sulcus dividing the branchial regions as we so commonly see in 
the short-tailed Anomura, and subsequently was gratified by the 
Woodwardian Inspectors with the sight of a little specimen of 
the N. Mantelli (M‘Coy) in the old cabinet left by Woodward 
to the University of Cambridge, showing the chelz and bases of 
all the feet, proving the posterior pair to be abruptly smaller than 
the preceding ones and elevated above them, and completely 
establishing the position of the genus: curiously enough, the 
entry of this specimen in Woodward’s MS. Catalogue indicates the 
same analogy with the recent form which Dr. Leach poimted out 
so many years afterwards. This genus includes the “ Corystes” 
of Leach and Mantell (Geol. Suss. p. 129. figs. 9 & 10), also the 
species figs. 13, 15, 16 of the same plate, and the “ species of’ a 
new genus allied to Arcania,” figs. 7, 8, 14 of the same plate, 
which is also the Orithya Bechet of Deslongchamps (Mém. de la 
Soc. Lin. de Normandie). Dr. Mantell in the above plate, fig. 15, 
shows a large joint in the abdomen below the fifth large one ; the 
specimen of the tail which I have seen is broken before the end 
of the fifth joint, so that I have no independent authority for the 
sixth joint or its mode of junction with the fifth, or whether the 
supplementary side pieces occur between them. 
Notopocorystes Mantelli (M‘Coy). 
Sp. Char. Greatest width of carapace (at base of gastric region) 
one-fifth less than the length ; three strong teeth on the an- 
tero-lateral margin, the middle one largest, placed at the end 
of the nuchal sulcus, the lower one between the first and the 
end of the faint branchial sulcus, at the end of which a fourth 
small tooth is found ; gastric region with a narrow mesial ridge 
from the rostrum bearing three small tubercles on its posterior 
half; each side of this region has a row of three tubercles 
running parallel with the gastric or nuchal furrow, the space 
between them being about equal to their distance from that 
furrow ; behind the inner tubercles of each row is one rather 
smaller ; the genital region bears one elongate tubercle in the 
middle ; cardiac and intestinal regions with a mesial ridge, the 
former bearing two large and the latter two small tubercles ; 
branchial regions with an obtuse boss close to their upper in- 
ternal angle, and two equidistant tubercles on each side in an 
oblique line to the second marginal tooth close under the 
