195 



The Drassus ater of most arachnologists is undoubtedly a col- 

 lective species, which in the first place includes that in central and 

 northern Europe most common species of the genus, M. subterranea 

 C. et L. Koch. That Latkeille's and Walckenaer's ') D. ater inclu- 

 des this species as well as M. atra L. Koch and M. petrensis id., I 

 consider as absolutely certain: I have specimens of all three species 

 from the neighbourhood of Paris, with which I have been favoured 

 by Simon. As however the specific name ater has by established 

 custom been assigned to that one among these species, which C. and 

 L. Koch call M. atra, that species ought to be allowed to retain the 

 Latreillian name. A far older name, that with equal certainty in- 

 cludes M. subterranea C. et L. Koch, is Ar. Petiverii Scop. C. Koch 

 accepts it without any reservation as a synonym to his M. subterra- 

 nea, and it is only to be regretted, that he did not at the same 

 time allow the species to retain the specific name that he rightly 

 considered as its eldest, and which we have no scruples in restoring. 



Drassus nigritus Hahn (Die Arachn., I, p. 123, fig. 93), is not a 

 sure synonym of M. Petiverii. It is stated to be nearly 5 lines long — 

 a length which is certainly never attained by M. Petiverii. Ar. ni- 

 grila Fabr., referred to by Hahn, belongs to M. pusilla C. Koch. — 

 Filistata atra Keuss includes only M. subterranea or Petiverii. 



Westring has under the name of M. subterranea united the two 

 species, which L. Koch calls M. subterranea and M. petrensis, as I 

 see from specimens which he has obligingly sent me. The spider 

 which is by Westring considered to be the same as M. petrensis C. 

 Koch (see following spec), is a third species, which has not been 

 described by L. Koch; it is therefore probably not = the true M. 

 petrensis, which cannot well have escaped the notice of L. Koch, 

 since, according to C. Koch, it is "not rare" in Bavaria. Westring's 

 determination of C. Koch's M. petrensis appears indeed to be streng- 

 thened by the circumstance, that the fore thighs in this spider are 

 by C. Koch said to be destitute of a pale transparent spot; but this 

 spot is sometimes wanting also in the M. petrensis of L. Koch, and 

 this author says (loc. cit., p. 167), that the want of such a spot is 

 "no constant mark for the species, for which it is by various authors 

 considered as a characteristic". — For these reasons I have, in pre- 

 ference to Westring's, adopted L. Koch's determination of the M. 

 petrensis of C. Koch. 



l) Faune Franc. Arachn., p. 162. 



