] 80 Gynandry in Arachnida 



§ Copyphaeina — 2 species. 

 Oedothorax fuscus Bl. 

 Oedothorax retusus Westr. 



§ Nerienina — 2 species. 



Maso sundevallii Westr. 

 Lophomma herbigradum Bl. 



Drassidae : 



§ Clubionina — 1 species. 



Agroeca proxima Cb. 



Kulczynski's Oedothorax was taken in Galicia in 1880 : the rest are 

 British (England, 7 : Wales, 1) ; and of these eight species seven belong 

 to one family, Linyphiidae. 



It is perhaps important to have a just conception of some reasons 

 why the Linyphiidae should take so large a place in this list. The 

 family is only one of seventeen represented in Britain ; but it is by far 

 the largest. I have just completed a revision of the British list of 

 spiders, and make the total of British species 539. Of these the Liny- 

 phiidae claim no less than 232 : proxime accessit, the Drassid family, 

 58 — exactly one-fourth of the Linyphiid total. Thus, of every 5 British 

 species, 2 are Linyphiids. In the north of England, which supplies 5 of 

 our 8 gynandromorphs, the proportion of Linyphiids is still higher; in 

 Northumberland quite a half Moreover, the family includes nearly all 

 the very small and critical species, which the collector finds it necessary 

 to take for closer examination. I shall not be over the mark if I say 

 that in an ordinary way 80 per cent, of my own captures (in Northumber- 

 land) are Linyphiidae. 



Still the difference in size of the sexes is so general that the conse- 

 quent asymmetry of the body, together with the conspicuous difference 

 of the palps (to say nothing of every collector's keen interest in practi- 

 cally every adult male !) would make it difficult for a gynandromorph to 

 be overlooked whatever family it belonged to. 



On the whole therefore we may conclude that the preponderance of 

 Linyphiidae in the records of gynandry fairly represents the actual state 

 of things. And, briefly, the British figures stand thus — in 232 species 

 of the Linyphiidae we have 7 cases of gynandry ; in 377 species of other 

 families 1 only. Taking the figures as they stand, they indicate that 

 cases of gynandry are a little more than nine times as frequent among 

 the Ijinyphiidae than in all the rest taken together. 



