Invertebrate Gallery of the Indian Museum. 6i 



In addition to the above there is exhibited a handsome 

 specimen oi Arcturus cornutus, Beddard, from the depths 

 of the Andaman Sea. 



iii. CRUSTACEA MALACOSTRACA CUMACEA. 



[ffl;i^0tn-n ®aU-r!t0e 54]. 

 The Cumacea is a small order of small Crustacea which 

 have a resemblance to some of the larval forms of the 

 Decapoda. 



This very limited order is represented in the Gallery 

 by a small specimen of Diastylis from Norway. 



Alongside of this specimen are shown for comparison 

 some larvae of a prawn {Penxus) in the Mysis stage. 



iv. CRUSTACEA MALACOSTRACA STOMAPODA. 



[»C0t£m ffltnll-fit0C0 49 anb 52], 



In the Stomapoda the abdominal region is greatly de- 

 veloped, forming a powerful swimming " tail", its append- 

 ages having the form of broad two-bladed swimming 

 plates. 



The segmental structure of this Order is so well dis- 

 played in the large dissected specimen of 5'^z<;///rt raphidea^ 

 in Case 49, that no further explanation is here required. 

 Observe that the first five pairs of thoracic limbs form 

 powerful chelate foot-jaws, those of the second pair being 

 of predominant size and being used for seizing and hold- 

 ing prey. 



In the spirit specimens observe the feathery gill-tufts 

 on the abdominal swimming plates. 



The Stomapoda are all marine, and are specially abun- 

 dant in the seas of the tropics : they are excessively pre- 

 daceous, seizing their prey with the second pair of thoracic 

 limbs, which on account of their great size and terrible 

 armature are known as the raptorial claws. 



