PALTNURUS OR THE SPINY LOBSTER OF BOMBAY. 365 



be the homologue of a process known as the cpipodite found on the 

 thoracic legs, but it differs in being attached by membrane to the 

 basipodite as well as to the coxopodite. Gills are attached to the 

 abdominal appendages of certain Copppods, another order of the 

 Crustaceee. 



In the male all the above appendages are much smaller and 

 have only one leaf, the exopodite, as the endopodite is quite 

 suppressed. 



Iirboth sexes the first abdominal segment is devoid of appendages. 

 Its tergum has a large buttress on each side just above the hinge 

 which prevents over-extension by coming in contact with the poste- 

 rior margin of the carapace. 



The lateral appendages of the sixth abdominal somite are very 

 large and with the telson form the powerful five-leaved tail fin. 



The protopodite consists of a single piece. The endopodite and 

 exopodite form two large oval plates, each with a proximal stout 

 oalcified. and a larger distal membranous portion. 



The telson may be regarded as a median appendage of the sixth 

 somite. Ventrally it is for the most part uncalc'fied. and in its 

 anterior portion is perforated by a longitudinal opening the anus. 



Two small oblique linear sclerites are seen on each side but some- 

 what in front of the anus. Dorsally the proximal portion is calcified 

 but the greater part is membranous. The proximal part of this 

 membranous surface as well as of the rest of the " tail-fin " is studded 



with minute spines. 



Cephalo-thokax. 



The dorsum and sides of the cephalo-thorax are covered by a large 

 unjointed shield, the carapace, which dorsally terminates in front 

 behind the eye-stalks by a broad crescentic notch limited at each 

 end by a stout spine which projects forward above and internal to the 

 eye. 



In front of the eyes is a broad plate firmly attached to and looking 

 like an extension of the carapace. This is not its true homology 

 however, and we will later on see that it is part of the united basal 

 joints of the antenna?. The dorsal part of the carapace bears a 

 number of sharp spines which project forward and are most of them 

 arranged in eight longitudinal rows. These sharp spines are some 

 compensation for the absence of the defensive pincers which Lobsters 



