■J]0 Frederich Chapman : 



btn-ings. It varies greatly in the proportional aciimination of the 

 post-ventral angle, and may be distinguished from .1/. decora by 

 rthe evenly-swollen sides and less flexuoiis upper and lower borders. 

 Dr. Brady gives as original localities for the living specimens, 

 Kerguelen Id., at 28 fathoms, and Wellington Harbour, New Zea- 

 land, from the tow-net at ti-awl. Dr. Egger obtained this 

 -species from the north-west coast of Australia, at 357 metres. 



Occurrence.— Bore 2. 198-200 feet (Kalimnan). Bore 4. 180-li)0 

 feet (Janjukian). Bore 8, 210-219 feet (Kalimnan or Janjukian). 

 Bore 9, 256-263 feet (Kalinuian or Janjukian). Bore 10. 310-320 

 feet (Kalimnan or Janjukian). Bore 11. 457-458 feet; 540-542 

 feet; 542-544 feet (Janjukian). 



Genus BYTH0CYPBI8. (i. S. Brady. 



JjYTHGCYPRIS tumefacta, sp. nov. (Plate VI., Figs, ia-c and 5). 



JJescripfion. — Carapace subreniform, very tumid. Seen from the 

 ;side, greatest height about the middle ; dorsal margin evenly 

 arched, ventral margin straight to slightly concave, with a faint 

 sinuousity in the middle; extremities rounded, the posterior rather 

 more acutely than the anterior. Left valve much larger than the 

 I'ight, overlapping all round. Seen from above, edge view sub- 

 oblong, anterior end sub-acutely rounded, the posterior bluntly 

 rounded. End view sub-circidar, ventral edge flatter than the 

 •dorsal. Surface smooth. 



Dimensions. — Holotype : Length, 1.125 mm.; breadth of caia- 

 pace, .575 mm. ; height, .575 mm. Paratype : A left valve. Length, 

 .95 mm. ; height, .5 mm. 



Affinities. — In outline this species is somewhat close to Bj/thn- 

 cypris reniformis, G. S. Brady, i from which' it materially differs in 

 its more swollen carapace and less reniform outline. It is interesting 

 to note, in common with the above comparison, that B. reniformis 

 is still living in Bass Strait, so that it is very probable that the 

 present species was the direct forerunner of the living Australian 

 form. 



Occurrence. — Bore 4, 163-170 feet (Kalimnan or Janjukian). 

 Bore 5, 189-190 feet (Janjukian). Bore 10, 310-320 feet (Kalimnan 

 or Janjukian). Bore 11, 342-349 feet; 450-452 feet; 540-542 feet; 

 546-548 feet; 552-554 feet; 554-556 feet; 556-558 feet; 558-560 feet 

 {Janjukian). 



1. Kep. Chall. Zool., vol. i., pt. iii., 1880, p. 4G, pi. v., figs. \a-L 



