1334 SPATiiA 



posterior end rounded, but somewhat produced a little below 

 the median line ; surface apparently finely, concentrically sculp- 

 tured ; epidermis reddish-brown, subshining; muscle scars 

 large, impressed, the two anterior ones confluent ; nacre pale 

 reddish. 



Length 77, height 2,^, diani. 24 mm. 

 Congo. 

 Spatha sinuata von Maktkns, S. B. Nat. Fr., 1883, p. 173; 

 Conch. Mitt., II, 1885, p. 190, pi. xxxiv, figs. 5, 6. — Simp- 

 son, Syn., 1900, p. 899. 



This species appears to differ from S. mabillei in its larger 

 size, the color of its epidermis and nacre, and in being more 

 elongated, von Martens' description is very brief and does 

 not touch on all the characters, but the figures are clear and 

 show a ditTerent style of anterior scars from any that I am 

 acquainted with. 



Spatha cERTii^LONiANA Preston. 



'"Shell moderately flat, rectangularly ovate, solid, scarcely 

 angled posteriorly, covered with a fine, reddish-chestnut peri- 

 ostracum, sculptured with coarse, broad, somewhat distant, 

 concentric growth-lines and very fine, transverse, radiate striae ; 

 umbones small, not prominent ; dorsal margin nearly straight, 

 somewhat ascending; ventral margin constricted towards the 

 middle ; anterior side squarely rounded ; posterior side broadly 

 produced, bluntly acuminate ; anterior adductor scars ovate, 

 well impressed ; posterior scars broadly ovate, moderately im- 

 pressed ; inf ra-umbonal visceral scars in right valve broad, in 

 left valve small, short and deep : pallial margin coarsely de- 

 fined ; interior of shell nacreous, pinkish-white, iridescent, es- 

 pecially towards the posterior side, sculptured with fine, inter- 

 lacing, irregular, wavy strire converging towards the centre 

 of the shell. 



Long. 51.5, lat. 07 mm." (Preston). 



Type locality, Karonga, north end of Lake Nyassa. 

 Spatha bertilloniana Preston, Ann. Mag. Nat. Hist., (8), VI, 



p. 63, pi. V, fig. 15. 



