37 



lobes, tlie middle one of •n-liicli is tlie true front and is the largest and most 

 prominent. The middle lobe again is slightly cleft at the tip, and in the cleft is 

 to be seen projecting the roof of the remarkably prolonged buccal cavity. 



The external orbital angle, which is somewhat ventrad in position, also forms 

 a jDrojecting tooth, so that the orbito-frontal region, which is sharply delimited 

 from the rest of the inflated carapace, has the form of a five-pronged crest or 

 crown. The regions of the carapace are plainly delimited, excepting only in the 

 case of the boimdary between the gastric and cardiac regions. The pterygos- 

 tomian regions are most remarkably puffed out. 



The abdomen in the female is large, and the terminal segment has the 

 form of a broad semicircidar plate, broader than any of the other segments and 

 nearly as long as all of them put together : in the male the abdomen is very 

 small. 



The orbits are capacious, but the eyestalks are slender and the eyes are 

 unpigmented and semi-opaque. 



The antennules, which are much larger and longer than the antennae, are 

 incapable of flexion beneath the front. 



The external maxillipeds are of great length, in correspondence with the 

 remarkable trough-like prolongation of the buccal cavity, which they completely 

 close in below; their meropodite, which is prolonged far beyond the insertion of 

 the palp, covers the bases of the antennules and antennaB, their tips in fact 

 being visible from above; the sleuder exopodite does not much surpass the 

 ischium. 



The chelipeds are short but massive, and are equal : the arm is curved, the 

 wrist is small, the palm is large and tumid, and the fingers, which are set almost 

 at right angles to the hand, are broad, compressed, pointed, very closely appos- 

 able, and have their cutting-edge very finely denticulated. 



The first two pairs of legs are of great length, being more than four times 

 the length of the body, the merus forming more than half their extent ; their 

 dactylus is filiform and is not much longer than their propodite. The last two 

 pairs of legs have the family position, but are mere rudiments, being of hair-like 

 tenuity and only about three-fourths of the carapace in length ; the last pair ends 

 m a hook-like dactylus, 



A female from the Andaman Sea, 405 fathoms, has the following dimensions: — 

 Length of carapace 6'5 miUim., breadth 6'5 millim., length of cheliped 9 millim., 

 length of second leg 28'5 millim., of fourth leg 4'5 millim. A male from the 

 Andaman Sea, 26.5 fathoms, is smaller. 



Coloiu- in the fresh state chalky pink. 

 6 



