290 JEGIDM. 



lowing joints of the pleon are large and broad, the 

 posterior lateral angles being produced into a curved and 

 acute point, we shall be convinced that Rocinela Danmo- 

 niensis is the type of a distinct genus, and that jfEga 

 monophthalma of Johnston, which M. Milne Edwards, 

 followed by Mr. A. White, introduces into the genus 

 Rocinela on account of the large size of the eyes, ought to 

 be referred to the genus Mga. This opinion is confirmed 

 by the descriptions of the mouth-organs given by M. Milne 

 Edwards in the Crochard edition of the " Regne Animal" 

 of the species which he terms Rocinela ophthalmica (giving 

 erroneously Leach as the author of the species), which 

 prove that that species is in fact an jEga, differing only 

 from Mga emargittata in the apparent soldering together 

 of the two terminal joints of the foot-jaws. 



