3G0 DR. BAIRD ON SEVERAL GENERA OF EUNTCEA. 



number of botli kinds (especially the pectinate setae) being 

 situated about the middle portion of the body. The two or three 

 anterior pairs of feet, and the two last pair, have the uncini or 

 booklets changed into the appearance of the compound setae of 

 Eunice, the falcate appendage, however, being as it were sol- 

 dered to the shaft and small — distinctly bidentate, as in Eunice. 

 The uncini are generally two in number to each foot ; but occa- 

 sionally there are three, and generally one is smaller than the 

 other. The caudal cirri show considerable variation also. In 

 general there are two ; but in one or two specimens examined there 

 were three distinct cirri, and in one specimen one of the two cirri 

 was divided, soon after it had sprung from the body, into two, or 

 became, as it were, dichotomous. 



From this variableness of the different portions of the body I 

 have assigned to it its specific name. 



Hah. St. Vincent's, West Indies, L. Guilding. 



The genus Hyalinoecia of Malmgren was first established by 

 Dr. Johnston, in his ' Catalogue of British IS^on-Parasitical Worms,' 

 in 1865, under the name of Nortliia. Malmgren changes the 

 name Nortliia to Notliria, and derives it from the Glreek word 

 vodpos, piger (slow ?). He says that Dr. Johnston must have 

 written it Nortliia in a mistake, unless he derived it from the 

 word North, in the same way as Dr. Grray formed his genus 

 Fromia (in Echinoderms) from the English preposition /row. I 

 suspect Dr. Johnston had no idea of deriving his genus Nortliia 

 from the English word Nortli (point of the compass), but that it 

 was intended as a compliment to a person of the name of North. 



In 1847 Dr. Gray named a genus of Mollusca Nortliia, taking 

 as the type a species of Nassa (iV. Nortliia), and so caUed it in 

 honour of a person of the name of North. As this genus of Mol- 

 lusks takes precedence by far in point of time of Johnston's genus 

 of Annelides, I think it advisable, though for a very difierent 

 reason from that given by Malmgren, to adopt this naturalist's 

 correction, and for the future write the name Notliria. Johnston 

 takes the species Onuphis titbicola as the type of his genus Northia, 

 and gives as his chief reason for forming the genus (separating it 

 from Onuphis) the fact that the two species referred to it are 

 destitute of pectinate branchia?, which exist in the species of the 

 genus Onuphis as adopted by Audouin and M.-Edwards, GTrube, 

 &c. Eor the Nortliia tuhicoJa of Johnston, Malmgren forms the 

 new genus Hyalinoecia, while as the type of the genus Notliria he 



