128 - Carcinological Fauna of India. 
than long and flattish. Branchial groove usually present, cervical 
groove sometimes present. 
Front broadly triangular, sometimes notched at tip. Antennal 
flagella not so long as the carapace. 
External maxillipeds typically opercular, completely closing the 
buccal cavern. 
Chelipeds equal or slightly unequal, generally much stouter than 
the legs. 
First three pair of legs stout, about as long as the chelipeds. 
Fourth (last) pair of legs dorsal and rudimentary. 
The abdomen in both sexes consists of 7 segments, and there is a 
pair of lateral platelets intercalated between the last two segments. 
The gills are phyllobranchize but sometimes show the transition 
from tricho- to phyllobranchie. The gill-plumes are 16 (?) on either 
side. 
Epipodites are present on the chelipeds and first three pair of legs. 
Sternal grooves of the female ending at the level of the genital 
openings. 
To this family belong (1) Dynomene and (2) Acanthodromia, both of which are 
represented in Indian Seas. 
Family III. Drommnpa, restr. 
Carapace variable, sometimes as long as or even a little longer 
than broad, sometimes slightly broader than long; generally strongly 
convex in both directions, sometimes flat; commonly ovoid or subcir- 
cular, occasionally pentagonal. 
* Branchial groove almost always conspicuous, the true cervical 
groove present or absent on the dorsum of the carapace. 
Front usually cut into 3 teeth, the middle one of which is always 
on a much lower plane than the others and is often of insignificant size 
or even absent: the front is rarely triangular, without lateral teeth. 
Antennal flagella shorter than the carapace. 
External maxillipeds typically opercular, completely closing the 
buccal cavern. 
Chelipeds equal, generally much stouter than the legs. 
First two pair of legs gererally stout, not much shorter than the 
chelipeds. 
Last two pair of legs generally much reduced in length and slender, 
subdorsal and prehensile. There is a tendency for the fourth (last) 
* The branchial groove of Bouvier, which by most authors is called the “ cervi- 
cal” groove. 
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