30 MR. F. O. PICKARD CAMBEIDGE OX THE [Jan. 18, 



Total length 17 mm. Carap. 7x6. Legs : i, 30 — ii. 30 — iii. 27 

 — iv. 32-5. Pat. + tib. i. 10— iii. 8-5— iv. 10-5. Prot. i. 6-5— iii. 6 

 — iv. 7-5. 



Colour. Carapace, legs, and abdomen ricli olive-brown. Carapace 

 with broad white band on each side submarginal, as far from 

 margin as width of band, not extending to the margin. Abdomen 

 with band of silyery-white on each side extending from the anterior 

 shoulders to the spinners. Ventral area pale yellow. 



Structure. Similar to that of T. unicolor. 



It is possible that this species is Thalassius fimbriatus (Walck.) 

 Sim., bat I can find no description which one can consider sufficient 

 for identification. The species of this genus apparently are very 

 closely allied, and in the form of the vulva are so much alike that 

 identification becomes a difficult matter. 



Vulva. See Plate IV. fig. Ih. A single female was taken by 

 Mr. H. A. Spencer at E. Loudon, South Africa, and is now in 

 the British Museum. Also another female from Sierra Leone. 

 I can detect no difference between the two specimens. 



Thalassicjs jayakaki, sp. n. (Plate IV. figs. 4, 9-11, & 14.) 



2 ad. 27 mm. Hah. Muscat, Arabia. Type in coll. Brit. Mus. 



Total length 27 mm. Carap. 10-5 x 8"5. Legs wanting in some 

 joints. Approximately the same as in T. phipsoni. Tibia i. 10*5. 



Colour. Carapace, legs, and abdomen the same as in T. phipsoni. 



Structure. Tibia i. as long as carapace. Vulva, see Plate IV. fig. 4. 



An adult female was taken by Mr. A. G. Jayakar at Muscat on 

 the Gulf of Oman, Arabia. Another adult female, much rubbed, 

 so that the white scales of the lateral bands have been obliterated, 

 was taken at Muscat by the same gentleman. 



TuALASSius cuMMixGi, sp. n. (Plate IV. fig. 3.) 



2 ad. 20 mm. Hub. ¥&o, Persian Gulf. Type in coll. Brit. 

 Mus. 



Total length 20 mm. Carap. 8x7. Legs: i. 35 — ii. 35 — iii. 

 34-iv. 40. Tibia i. S. 



Colour. Carapace and legs red-brown, clothed with fine 

 grey pubescence, the former with two latei'al bands of white 

 scales, not extending laterally to the margin. The base of each 

 of the spines on the legs is set in a dark brown spot. Abdomen 

 delicate olive-ochreous, clothed with fine grey pubescence, having 

 a narrow band of white scales on each side ; these bands, both on 

 the carapace and the abdomen, are margined with a rich brown 

 line. Protarsi fringed with fine hair. 



Structure. Tibia i. as long as carapace. Vulva, see Plate IV. 

 fig. 3. 



An adult female of this beautiful species was taken by Mr. W. 

 G. Gumming in the Persian Gulf. This gentleman has been good 

 enough to contribute valuable data on the habits of this spider, 

 thus giving us a knowledge of the habits of the genus, which 



