164 CALIFORNIA ACADEMY OF SCIENCES. 



crotalus (Zool. Garden of Rotterdam) and consanguineum 

 (Les Pediculines, Supplement, 1885, P- IT 6> pk xii, fig. 

 7) found on P. erythrorhynchus (dried skin in Museum 

 of Leyden). Picaglia has described a third species rag- 

 azzi (Atti d. Soc. d. Nat. d. Modena, 1885, serie iii, vol. 

 ii) found on P. trachyrhynchus (Callao), and has estab- 

 lished the subgenus Piagetia for the group. The char- 

 acters of the subgenus are as follows : " abdomen narrow 

 and very elongate; male longer than female; length more 

 than 5 mm." The remaining members of the genus 

 Menofon present in contrast these characters : " abdomen 

 oval-elongate, rounded oval, or almost round ; male smaller 

 than the female; length varying from 1 to 3 mm." The 

 species chiefly used by Franz Grosse in his study of the 

 anatomy of the Mallophaga was a member of this Meno- 

 pon titan group, taken from a Pelican, undetermined, 

 from Chile. 



It certainly seems advisable to indicate the peculiar 

 characters of the group by assigning to it a subgeneric 

 name; but I can hardly recognize in Picaglia's descrip- 

 tion of rao-azzi characters other than the dimensions 



o 



which make it recognizably distinct from titan. My 

 specimens from Pel. erythrorhynchus show the slight vari- 

 ations from titan indicated by Picaglia in his description 

 of ragazzi, but the dimensions are quite as large as those 

 of titan (Picaglia made ragazzi one - fourth shorter than 

 titan) ! My specimens from Pel. calif ornicus closely cor- 

 respond with Piaget's description of titan, except that the 

 transverse abdominal blotches are not bifurcated at the 

 extremities. I believe that the present knowledge of the 

 group hardly justifies any separation of the known forms 

 into distinct species, but that the presence of these varia- 

 tions may be recognized by letting titan stand as the rep- 

 resentative form of the species (consanguineum is evidently 

 a distinct species, the equality in size of both sexes re- 



