44 THE VOYAGE OF H.M.S. CHALLENGER. 



a third, Chlorida decorata, Wood-Mason, is very briefly and inadequately described, 

 and the fourth, Chlorida microphthalma, E. and S., by no means satisfactorily known. 



Our species would belong to the genus if the shape of the eyes were the criterion, but 

 it is so perfectly connected with Squilla fasciata, a true Sqidlla, through the species 

 which was last described, Squilla lata, that the propriety of retaining the genus Chlori- 

 della must remain very doubtful for the present. A comparison of this species (PL II. 

 fig. 1), Squilla lata (PL III. fig. 1), and Squilla fasciata (PL III. fig. 4), wUl show 

 that no one of these three species should be placed in a genus which does not include 

 the other two, and as the last is clearly a true Squilla I have included all three in this 

 genus. 



The comparative table of measurements of the three species which is given at the 

 end of the description of Squilla fasciata will also serve to show the close resemblance 

 much better than a description. 



Genus I/ysiosquilla, Dana. 



Diagnosis. — Stomatopoda with the sixth abdominal somite separated from the 

 telson by a movable joint ; the hind body depressed, loosely articulated and wide ; the 

 dactyle of the raptorial claw without a basal enlargement, but with more than six 

 marginal spines ; no more than four secondary spines, and often only one, between the 

 intermediate and submedian sj)ines of the telson, which is usually wider than long ; and 

 the outer spine of the ventral prolongation from the basal joint of the uropod usually 

 longer than the inner. The larva is an Erichthus or Squillenchthus, with the ocular 

 and antennulary somites covered by the carapace ; the lateral edges of the deep carapace 

 folded inwards over the ventral surface ; the bases of the postero-lateral spines distant 

 from the dorsal middle line ; the hind body flat and wide ; the telson wider than long, 

 and with few spines or only one between the intermediate and submedian spines ; and 

 the dactylus of the raptorial claw with numerous marginal spines. 



Special Description. — I have examined the first abdominal appendage of the males 

 of twq species, Lysiosquilla tnaculata (PL X. fig. 6) and Lysiosquilla excavatrix (PL 

 X. fig. 12), and find such great and characteristic diff'erence from Squilla, that I 

 do not hesitate to add to the diagnostic characteristics of the genus the statement that 

 Lysiosquilla is distinguished by the fact that the terminal joint of the exopodite of the 

 first abdominal appendage of the adult male is subtriangular, with its large outer lobe 

 separated by a suture from the very smaU inner lobe, and the fixed Hmb of the petasma 

 very small and not ending in a hook. 



Like the genus Squilla the genus Lysiosquilla includes two minor groups, a highly 

 specialized one and a more primitive and slightly modified one. The single specimen of 

 Lysiosquilla (Coronis) scolopendra upon which Latreille based his genus Coronis, was 



