150 LJuly, 



Aqeion c^ieulescens, Fonsc. Albarracin, 5 J , T. A. C, G-. C. C. 



Ageion mekcueiale, Clip. Cuenca and Brouchales, 3 3 , T. A. C. 



Agbion Lindenii, Selys. Cuenca, 1 g , T. A. C. 



Pyeehosoma nymphula, Sulz. (minium, Harris). Cuenca, Tragacete, Hron- 

 chalos, Albarracin, many examples, T. A. C. 



Lestes deyas, Kby. (nympha, Selys). Cuenca, Brouchales, Albarracin, 8 <J , 

 3 ? , T. A. C. 



Lestes vieens, Clip. Albarracin, 1 <J , T. A. C. 



SYMPYCNA FUSCA, V. d. L. Cuenca, T. A. C, G. C. C, many examples. 



Lewisham, London : 



May Uth, 1902. 



NOTES ON THE FEMALES OF ARCTIC AND NORTHERN SPECIES 

 OF A PAT AN I A (Plate III). 



BY KENNETH JOHN MORTON, F.E.S. 



Id dealing with Trichoptera from a purely systematic point of 

 view, it has been the practice, unacknowledged, I think, and perhaps 

 unconsciously followed, to give less attention to the study of the 

 females than to the other sex : at least this applies in my own case, 

 if any other worker objects to the general statement. iSueh a practice 

 is without difficulty accounted for. The examination and comparison 

 of the wonderfully complicated appendages of the males are at once 

 comparatively easy and interesting, while in the females the parts are 

 simpler, they apparently vary less amongst the species, are without 

 striking points in structure, and, most difficult feature of all, in 

 drying the parts shrink much and very unequally. 



In the genus Apatania the females have an importance which 

 does not permit of their being ignored, or even of their being dealt 

 with in a superficial way. The occurrence of parthenogenesis in the 

 genus must be regarded as pretty well established, and two species 

 have been described which, so far, have only been found in the $ sex. 

 And in addition to the difficulties imported into the genus by the 

 existence of species of which only females are found, there is the 

 further difficulty— one probably indirectly connected with the 

 phenomenon of parthenogenesis— that one sometimes meets with 

 quantities of females unaccompanied by males in a given locality. 

 For instance, Apatania Wallengreni may sometimes be taken in large 

 numbers, the percentage of males being very small, and in some 

 gatherings apparently of this species males are absent altogether. 

 It may be that in such eases the percentage of males has originally 



