438 Mr. R. I. Pocock on Arachnida from the 



with the typical form, the posterior lateral spines being on 

 an average thinner and with less of a posterior curvature. 

 This character, however, is not, I think, sufficiently definable 

 to admit of being regarded as the basis for a subspecific form. 



Gasteracantha macrura, sp. n. ((PI. XIII. fig. 3.) 



Somewhat intermediate in structural characters between 

 G. milvoides and the species which I identify as G. ensifera, 

 Thorell, but readily distinguishable from both. 



Abdomen with anterior border lightly convex, the anterior 

 lateral spines considerably the smallest of the six, directed 

 externally, their length a little less than the width of the 

 head and greater than the interval that separates these spines 

 from the posterior laterals ; posterior laterals very long, 

 straight, thick, thickly hairy, nearly as long as the width of 

 the abdomen, and nearly three times as long as the width of 

 the head, a little more than three times as long as the anterior 

 lateral spine, and a little more than twice as long as the 

 posterior spines ; posterior spines long, much longer than 

 width of head. 



Measurements in millimetres. — Width of head 3 ; length of 

 patella and tibia of first leg 3'5, of fourth leg 3*3 ; length of 

 abdomen along the middle line b' 5, width between spines 11, 

 width from tip to tip of anterior lateral spines 14'5, of poste- 

 rior lateral spines 28 ; length, including posterior spine, 9 ; 

 length of anterior lateral spine 2'3, of posterior lateral spine 

 almost 9, of posterior spine 4. 



Loc. Nyasaland [Universities' Missioii). 



Resembling G. milvoides and differing from ensifera in 

 the great length of the posterior lateral spine, and differing 

 from milvoides and somewhat resembling ensifera in the 

 length of the posterior spine. 



Family Pisauridae. 



Genus EUPROSTHENOPS, PoC 



Exiprosthe7iops australis, Simon. 

 Euprosthenops anstralis, Simon, Ann. Soc. Ent. Belg. xlii. p. 12 (1898). 



Loc. Nyika plateau, 6000-7000 feet (A. Whjte) ; Lake 

 Nyasa [Universities' Mission) ; Lake Tanganyika [A. 

 Carson) . 



The Nyasaland examples of this genus that I have 

 examined agree with M. Simon's description of E. australis 

 and differ from his description and from Capello's figure of 



