192 T. THORELL, 
4 teeth. In the large burrowing species, e. g. 7: melanogaster (LATR.) or 
JNarbonensis (WALCK.), the free point of the claw is longer and bent more 
deeply downward than in the smaller species found in north and central Eu- 
rope. In 7. melanogaster, the palpal claw has 4, the superior tarsal claws 
5 or 6 teeth in the first half of their length. Also in 7' Apulie these 
latter claws are armed with 5 strong comb-teeth, according to BERGSOE !). 
Gen. 4. TROCHOSA (€. Koch). 1848. 
Deriv.: zooydw = wvoéyo, run. 
Syn.: 1805. Lycosa Warck., Tabl. d. Aran., p. 10 ("1* Fam. Les Terricoles, Zerricole” 
ad partem). 
1833. » + Sub-gen. Tarentula Sunp., Consp. Arachn., p. 24 (ad partem). 
1848. Trochosa C. Koch, Die Arachn., XIV, p. 95. 
1848. Arctosa ID., ibid., p. 94. 
1861. Lycosa Wesrr., Aran. Suec., p. 467 (ad partem). 
1861. »  Buackw., Spid. of Gr. Brit., I, p. 16 (ad partem). 
1864. Trochosa Srw., H. N. d. Araignées, p. 345. 
Type: 7. ruricola (DE GEER). 
I have not been able to discover any feature depending on difference 
of form, whereby Arctosa ©. KocH may with certainty be distinguished from 
Trochosa 1D., and I therefore follow SIMON in uniting these two genera in 
one, under the latter name. A difference might perhaps be shown to exist 
in the form of the claws, but it does not appear to me advisable to found 
a genus on a characteristic, that can only be discerned by the aid of the 
microscope. In the species of Arctosa that I have had the opportunity of 
examining (A. cinerea C. KocH, A. picta ID., Lyc. leopardus SUND.), the superior 
tarsal and the palpal claws have their toothless extremity considerably longer, 
and eurved more deeply downwards, thau in most other Lycosoidze, at least 
on the fore legs: the superior tarsal claws are provided with teeth through- 
out their first half only, and on the palpal claw the teeth are seated still 
nearer the base. This form of the claws is, I suppose, connected with 
these spiders’ more fully developed ability of digging themselves cylindrical 
holes or galleries in the earth. (Conf. preceding genus, Tarentula). In T. 
(A.) cinerea I have met with about 10 teeth on the superior tarsal claws 
of the 1°, and 12 on the 4" pair of legs, those most external being bent 
somewhat forward, all of about equal length; the inferior claw is small and 
1) Iagttag. om den Ital. Tarantel ete., p. 245. 
