414 APPENDIX. No. IV. 



peduncles to its eyes, which are inserted into the same part of the shell as 

 in that genus. 



Ptlumnus, (a new species.) Gulph of Guinea. 



Grapsus minidus, and a new i5pecies. Gulph of Guinea. 



Dorippe. Species not determined. 



Sp. 1. Megalopa* Cranchii (new species) with a broad, entire, porrected 

 rostrum, having its point terminating in one spine, and each side armed 

 with a tooth, hinder coxae armed with a straight spine. Gulph of Guinea. 

 This species belongs to the same division of the genus vnth those of our seas. 



Sp. 2. Megalopa maculata. (new species) Shell smooth, and spotted with black, 

 rostrum narrow and abrubtly deflexed. 



Sp. 3. Megalopa sculpta. (new species) Shell sculptured (like that of Cancer 

 floridus Herbst) and very hairy, rostrum narrow and abruptly deflexed. 

 Obs. These two species were hkewise taken in the Gulph of Guinea; 

 they form a new division of the genus characterised by the deflexed 

 rostra. 



Scyllarus. Of this genus, a common species was taken during the voyage, and 

 having been pi-eserved in spirits, allowed me to ascertain by dissection, that 

 its nervous system is in all respects similar to that of the other macrourous 

 Crustacea. Its lamelliform broad antennas send their nerves to the same 

 gangUon. The optic ners'es are more curved in their course. 



Of the large group of macrura comprehending the shrimps and prawns there 

 are eleven new species, and seven new genera. 



A new genus allied to Nebalia. 



Zoea. The type of this genus was discovered in the Atlantic by Bosc, who 

 believed it to hold an intermediate situation between the Crustacea with pedun- 

 culated, and those mth sessile eyes. By Latreille it was referred to the 

 Entomastraca. In N. lat. 1, 36, E. long. 8, 46, 37, Mr. Cranch took a 

 new species of this interesting genus, by which I have been enabled to verify 

 the opinion published in the Supplement to the Encyclopaedia Britannica, 

 (vol. i. p. 423) where I have referred it to the Crustacea with pedunculated 

 eyes. 



* The last segment of the abdomen on each side is furnished with two moveable 

 plates, which I formerly overlooked. 



