1 3 [ Miscellaneous. 



C. B. Wilson. North- American Parasitic Copepods belonging to the 

 Family Caligidae. — Parts 3 & 4. A Revision of the- Pandarinae and 

 Cecropinae. Proc. U.S. Nat. Mus. vol. xxxiii. pp. 323-490, 



plates xvii.-xliii. December 1907. 



The parasitic Copepoda are a group of which the study is rendered 

 particularly difficult by the great changes which take place during 

 growth, by the remarkable and varied sexual dimorphism, and by 

 the absence, in recent years, of anything like a serious revision of 

 the group or of any considerable part of it. This last difficulty 

 Dr. Wilson has courageously set himself to remove in the series of 

 memoirs of which this is the latest. That his work will be of very 

 great value to future students cannot be doubted. The material 

 at his disposal is larger than in the case of most earlier writers ; he 

 has been able to examine and to identify the larval stages of a 

 number of species in the different subfamilies; the figures which 

 he gives are numerous, and, if somewhat inartistic and lacking 

 in detail, are clear and apparently accurate. It is much to be 

 regretted, however, that a little more trouble was not taken at the 

 outset to make quite clear the relation between the morphology of 

 the parasitic groups and that of the free-living forms. Dr. Wilson 

 recognizes " twelve pairs of appendages, namely, two pairs of an- 

 tennae, one pair of mandibles, two pairs of maxillae, two pairs of 

 maxillipeds, and rive pairs of swimming-legs." How this series of 

 appendages is to be compared with that of the typical free-swimming 

 Copepods we are uot told, nor is it easy to guess. YV. T. C. 



MISCELLANEOUS. 



The Genotype of Cidaris. 



To the Editors of the Annals and Magazine of Natural History. 



Gentlemen, — Dr. H. L. Clark's able advocacy of his views in the 

 June number of the 'Annals' helps to make clear the precise 

 difference between us. 



Except for a few advocates of pre-Linnean and non-binominal 

 names, we all agree to ascribe Cidaris to Le^ke. It follows by the 

 rules that the genotype must be one of the species assigned by 

 Leske himself to Cidaris. Being unable to discover on what 

 grounds other authors had selected C. papillata, I applied the rubs, 

 and found these to lead to the same result. Rightly or wrongly, 

 Dr. Clark accepts no other of Leske's species as a Lidaris at all, and 

 is theretore bound either to accept G. papillata or to reject the 

 generic name. Essentially he does accept it, and it is with the 

 next step that trouble begins. 



We all agree that Leske's sections I., II., aud III. represent three 



