172 Gynandry in Arachnida 



generally called, may briefly be described as a more or less elaborated 

 syringe, capable of sucking up the seminal fluid ^ and expelling it again 

 gradually in the act of coition. The corresponding article of the female 

 is a plain cylindrical joint more or less acuminate at the apex. 



3. Other characters. So far as the species enumerated below 

 are concerned these are all associated with the cephalic region, including 

 the pair of prae-oral appendages (falces or mandibles). Up to the time 

 of the penultimate moult these differences do not show (nor any other, 

 as a matter of fact) ; but as the final moult approaches, the tarsus of the 

 male palp enlarges rapidly, and in the case of the Linyphiidae (to which 

 family belong nearly all species now to be dealt with) there is often a 

 special development of the male caput, and of the form and armature 

 of the falces. 



ii. Gynandromorphs of three species have been figured and de- 

 scribed : 



Oedothorax fuscus Bl. {sub Erigone fusca). Kulczynski, PoiworeA; 



Obojnakowy Pajaka, Cracow, 1885. 

 Maso sundevallii Westr. Falconer, Naturalist, 1910, p. 229. 

 Lophomma herbigradum Bl. Hull, Trans. Nat. Hist. Society of 



Northumberland, etc.. Vol. iv. (New Series), p. 48. 



No two of these agree, as it happens, in the distribution of sexuality, 

 and they may be regarded therefore as types of three different classes. 

 I take them in order, as above. 



1. One side male, the other female — sexual structures perfect except 

 for the distortion resulting from the union of dissimilar halves on the 

 median line. 



Of this Kulczynski's Oedothorax fuscus is an excellent example. 

 I translate his description, and add some of his figures. 



The right half of the cephalothorax is longer and wider than the left (width: 

 380 /i, left 350/x; length from fore middle eyes to the hind margin: right 970 /x, 

 left 910;:i), the difierence mainly accounted for by the asymmetry of the hind margin, 

 of which the shape is shown in Fig. 1. 



The eye area is slightly asymmetrical, the right eyes being a little in advance of 

 the left : what difference there is in the size of the corresponding eyes is hardly per- 



1 The peculiar interest of this operation will excuse a note. I have twice witnessed 

 the exclusion of the seminal fluid. In each instance it was deposited on a leaf — the living 

 leaf of a tree in the case of Linyphia montana, a dead leaf on the ground in the case of 

 Lycosa amentata ; in both cases it was immediately taken up into the bulb. Coition was 

 effected a few minutes afterwards in the former case ; in the latter I could only watch 

 about half-an-hour, and courtship was still proceeding when I left. 



