b 



from the Lower Aviazons &c. 101 



stretched out before and behind along the stem, being veiy 

 difficult to see owing to the exact similarity of their colour to 

 the pale yellow withered grass-blades. When alarmed they 

 would run with ease and great rapidity on the surface of the 

 water, diving below or running down the grass-stems beneath 

 the surface if hard pressed. The Dolomedine habits and 

 genera] structure of this species and another much larger form, 

 of which I was unable to get adult specimens, and therefore 

 hesitate to describe, are very noteworthy. (PI. IV. fig. i. b.) 



Part III. — Crihellate " Ctenoid ^^ Forms referred hy Simon 

 to Fam. Zoropsidse, with two tarsal claws ; Notes and 

 Descriptions of new Species from the JSew World. 



Family Zoropsidae, Simon*. 

 Subfam. AcANTSOCTENiNJE, Sim. 



Genus ACANTHOCTENUS, Keys., 1877. 



Diagnosis. — Eye-formula " Ctenoid." Ocular quadrangle 

 scarcely longer than broad ; anterior side narrower ; anterior 

 centrals smaller than posterior centrals ; second row procurved. 

 Clypeus as high as twice the diameter of anterior centrals f. 

 TibiaB i. and ii. with 7-9 pairs of very long spines beneath 

 and 3-4 spines on each side. Protarsi i. and ii. with five 

 pairs of long spines beneath ; no central apical spine beneath. 

 Patella and tibia i. much longer than iv. Legs (1, 4) — 2, 3. 

 Tarsal claws 2. Calamistrum and cribellum present. Lower 

 margin of fang-groove with 3 teeth, upper with 2. 



This genus was formed for the reception of two Cteniform 

 species, A. sp^mpes, Keys., from Bogota, and A. spinigerus, 

 Keys., from Cordova, .Aiexico, in 1877. 



M. Simon has pointed out (Hist. Nat. Ar. i. p. 229) that 

 these spiders having the calamistrum and cribellum belong 

 more properly to his family Zoropsidre, under the subfamily 

 Acanthocteniiiae. He also says tliat the species referred to 

 this genus by Thorell (Ann. Mus. Gen. 1890) ttc. — A. varia^ 

 tus, dimidiatus^ and Icetus — belong to the Cteuinee. 



The type of this genus has been selected by M. Simon, 



• This classification is adopted provisionally. 



t M. Simon says (Ilist. JSat. Ar. i. p. 229) : — "Clypeus oculis anticis 

 non multo latior." If the comparison is with the diameter of the eyes it 

 is incorrect, but if with the transverse space occupied by the eyes it is a 

 pity it is not clearly so stated. I'ig. 178, p. 227, is, however, correct ia 

 this respect. 



