4 ON NEW AND BARE BRITISH SPIDERS. 



GENUS NERIENE, SI. 

 NERIENE PROMISCUA, Cambr. (Spid. Dors., p. 482.) 



Two males wcro found by F. 0. P. Cambridge, among soa- 

 weod on the shore at kighwater mark, at Polperro, Cornwall, in 

 June, 1883. 



NERIENE ATRA, BL (Cambr., Spid. Dors., p. 106.) 



In the summer of 1883, Mr. F. M. Campbell pent to me 

 from Hoddesdon an adult male spider, well developed and 

 fully coloured, evidently nearly allied to Neriene atra, Bl., but 

 differing from it in wanting the full characteristic development of 

 the armature of the cephalothbrax and falces, as well as in the 

 length and proportion of tho joints and apophyses of the palpi. 

 I subsequently met with two other examples in the neighbour- 

 hood of Bloxworth, showing a similar departure from these 

 typical characters. 



Under ordinary circumstances tho differences above noted would 

 have boon legitimately considered sufficient for the characteriza- 

 tion of these examples as a new species, but having submitted 

 one of them to Mons. Eugene Simon (one of the most 

 experienced of living araneologists), ho agrees with me that 

 it is only an abnormal, or not fully developed (though completely 

 developed so far as its own individuality is considered), form of 

 Neriene atra, Bl. 



I would now suggest that in very abundant species (like 

 Neriene atra} the occasional occurrence of undeveloped individu- 

 als pojnts to the probability of a now species in process of for- 

 mation. Whatever the cause or causes may be of the present 

 production, here and there, of such undeveloped examples, those 

 causes may bo well supposed to continue, and very possibly to 

 become intensfied ; the law of inheritance would then come 

 in and operate in the same direction, and thus a more constant 

 succession of such forms would be produced. For tho students 

 therefore of tho future we may anticipate that there would bo a 



