X PREFACE. 



the endopod of the second ph^opod in the male carried a stylet. The 

 females had the transverse foramen, which constituted the proximal 

 part of the abdominal notch, just as did the males. With this modifica- 

 tion of Hansen's genus Dymimeth^la^ of which he makes Dynamene 

 perforata the t^^pe, I can then refer to it the following- species: Dyna- 

 viene henedlcti, Dynaiuene glahra,, and Dynariiene inoorei. The follow- 

 ing shows these relations more exactly: Dynamene pei'forata—Dyna- 

 menella perforata; Dynamene henedlctl = DynaineneUa henedictl ; 

 Dynamene glabra = Dynanienella glabra; Dynamene rnoorel = Dyna- 

 rnenella moorei. Inasmuch as only females are known of Dynamene 

 angulata and Dymimene dilatata^ it can not be stated positively 

 fli^diether thej' should be referred to Dynamcnella or DaracerceU. 

 Doctor Hansen says that, judging from the aberrant shape of the 

 antennulge, D. dilatata must probably be established as the type of a 

 new genus. 



In I'egard to Cilicxa lingwicaada and Cillcxa granulosa^ Doctor 

 Hansen says that the former is probably, the latter perhaps, a species 

 of Cymodore. Upon an examination of the pleopods subsequent to 

 the printing of my paper and the publication of Doctor Hansen's I 

 find that these two species not only should not be referred to the 

 genus Oymodoce^ but not even to the section C.ymodocini or to the 

 group Sphterominje hemi branchiate. Both branches of the fourth 

 pair of pleopods are similar, fleshy, with transverse folds, without 

 plumose seta^, and the outer branch is not two-jointed. These two 

 species, therefore, belong to the group Sphajromiua? eubranchiatte. 

 In these species the exopod of the third pleopod has an articulation, 

 and is therefore two-jointed. The character of the abdominal notch 

 without paired denticles would seem to exclude them from the genus 

 Paracerceis as restricted by Hansen. The character of the uropods, 

 which are strongly altered, would exclude them from the genus Cer- 

 ceis Milne Edwards. Thev can not be placed with IlasicelUa Miers, 

 because they lack the large, mesial process on the sixth thoracic seg- 

 ment. It will be necessary to establish a new genus for these two 

 species, for which I propose the name Discerceis^ C. granulosa being 

 the type. 



Doctor Hansen does not mention (JUiceea carinata in his discussion 

 of the species of this family. Upon examination, I find that the 

 branches of the fourth pleopoda are similar, fleshy, crossed with trans- 

 verse folds, the outer l)ranch l)eing unjointed. The outer branch of 

 the third pleopod is also unjointed. Although the onl}" specimen is a 

 male, judging from the charactei" of the uropods and their similarity 

 to the males of other genera in this family, there is no stylet attached 



