370 Dr. W. T. Caiman on 



Jersey ") and its filamentary appendages have not been 

 described, it seems advisable to record the Oriental form 

 under another name. The larger specimens exceed in size 

 any hitherto described in the genus. 



Megalasma (Glyptelasma) carinatum (Hoek). 



Meqalasma {Glyptelasma) carinatum, Caiman, Ann. & Mag. Nat. Hist. 

 (9) i. 1918, p. 401, figs. 1-3 (with references). 



Locality.— Lat. 14° 54' N., long. 23° 42' W. (Cape Verde 

 Islands), 990 £ath. C./S. 'Britannia.' 1 specimen. 



Megalasma (Glyptelasma) hamatum, sp. n. 

 (Text-tigs. 5, 6, and 7.) 



Localities. — 

 Atlantic : 



"Off coast of Cuba" (with specimens of M. earinatum). 

 2 specimens. 



Lat. 14° 54' N., long. 23° 42' W. (Cape Verde Islands), 

 990 fath. (with specimens of M. carinatum). C./S. ' Brit- 

 annia. ' 1 specimen. 

 I ndo- Pacific : 



Lat. 6° 58' S., long. 39° 16' E. (near Zanzibar), about 

 270 fath. C./S. ' Sherard Osborn.' 1 specimen, 



Lat. 8° 46' S., long. 114° 44' E. (Java-Australia), 400 

 fath. C./S. ' Recorder.' 2 specimens. 



Lat. 11° S., long. 121° 30' E. (Java- Australia), 500 fath. 

 C./S. ' Patrol.' 2 specimens. 



Lat. 11° -S., long. 122° E. (Java-Australia), 600 fath. 

 C./S. 'Patrol.'' 7 specimens. 



" Victoria-Tasmanian cables, north end." C./S. ' Re- 

 corder.' 2 specimens (including holotype). 



Lat. 37° S., long. 165° E. (Tasman Sea), 800 fath. C./S. 

 ' Patrol.' 1 specimen. 



Description. — Cuticle thin, only present near edges of 

 valves. Valves rather thin, lines of growth and radial stria- 

 tions not strongly marked ; all valves in contact or nearly 

 so. Scutum with occludent margin convex, tergal margin 

 straight, carinal margin convex above, more or less deeply 

 concave or notched below, basal margin straight, forming a 

 right or an obtuse angle with the chord of the occludent 

 margin ; submarginal ridge from umbo to apex straight or 

 gently curved ; ridge from umbo to carino-tergal angle very 



