64 Mr. \V. F. K\rhy~Xotes on ForficiilIfL^. 



the forceps, while the females are scarcely distinguishable. 

 At present it is uncertain how far this may be a case of sexaal 

 polymorphism resembling that of the genus Forficula, L., 

 itself (more remarkably in Odontolabis, Hope, in the Coleo- 

 ptera, and Iliades, Hiibn., and other Equitine genera in the 

 Lepidoptera), or whether the various forms represent closely 

 allied but really distinct species. 



Group of Labidura riparia. 



Much confusion has been caused in this group by Dohrn 

 and De Bormans treating most of the forms belonging to it 

 as subspecies of L. riparia, and distributing the various names 

 applied to them under these subspecies, without any regard 

 to the original localities and descriptions. Hence the idea 

 that L. riparia is a very variable species, occurring all over 

 the world. The pale typical form described by Pallas from 

 AVestern Asia is found also in South Europe, North Africa, 

 and perhaps in other parts of Africa ; but I doubt if it is 

 indigenous in either South-eastern Asia or America. A large 

 amount of material and, perhaps, breeding experiments would 

 be necessary to throw full liglit on the question ; but in the 

 meantime the following preliminary notes may be useful : — 



1. L. he7\gahnsis, Dohrn. 



Very distinct from any otlier form in the shape of the 

 forceps in the male, and usually also in the female, but some 

 small females, in which the inner edge of the forceps is less 

 crenulated than usual, somewhat approach large females of 

 L. riparia, in which this character is more conspicuous than 

 usual. 



Tiiere is a broken specimen from Sokotra, perhaps belonging 

 to this species, in the collection, and a very dark female, 

 agreeing better with this species than with any other, from 

 Portugal, collected by Rev. A. E. Eaton. 



2. L. riparia^ Pall. 



Undoubted synonyms of the typical form of this species 

 are gigantea, Eabr., bili/ieaia, Herbst, maxima, Vill., and 

 morhida, Scrv. All other alleged synonyms are more or 

 less doubtful, 



Var. mixta, Bol. 



From Cadiz. Distinguished by having a double black line 

 on the abdomen both above and below. An immature speci- 

 men in the Museum from Spain has the double line above, 

 aud probably belongs to this form. 



