400 MAZATLAN UNIVALVES 
with denticles inside ; notch deep but narrow. Whirls rounded, 
with 11—18 radiating coste, decussated by spiral strie, of 
which about 5 shew on the upper whirls. Long. °38, long. 
spur. °23, lat.°17, div. 32°. 
Hab.—Gulf of Nicoya; 18 fm. mud ; Hinds.—Mazatlan ; 2 sp. 
only ; L’pool Col. 
Tablet 1912 contains the largest specimen. 
472. CLATHURELLA AUREA, %. s. 
Cl. t. valde attenuata, aurea, epidermide tenut, interdum 
aurantia, tinctad ; anfr. 1x. convexis, canali infrasuturali latiore, 
lineis incrementi arcuatis distinctis ornato ; tuberculis coste- 
formibus viil.—x. rotundatis in. peripheriam, secundum lineas 
spirales, lil. in spird, tuberculatis ; anfr. ult. costulis radianti- 
hus infra tuberculos confertis, lirulis confertis spiralibus tuber- 
culatis ; apertura et canali subelongatis ; labro varicoso, crasso, 
intus dentato; sinu postico profundo, angusto, spiram subascen- 
dente, supra calloso ; labio tenwi, dentato. 
Approaches Cl. bicanalifera, Sow. but differs in the narrow 
slit, and singularly decussated groove. The varix is extremely 
thick. The costular tubercles which appear on the spire, do 
not correspond with the narrow crowded ribs which appear on 
the basal portion. Jt is more slender than Cl. rava, with dif- 
ferent colour and sculpture. Long. °54, long. spir. *26, lat. *18, 
div. 25°. 
Hab.—Mazatlan ; 1 fresh specimen ; L’pool Col. 
Tablet 1913 contains the specimen. — 
Genus MANGELIA, Risso. 
Hist. Nat. Fur. Mer. vol. iv. p. 219, 1826 :—do. Leach, ms.— 
H. & A. Ad. Gen. vol. i. p. 99. (Non Mangelia, Rve. Conch. 
TIe.=Cithara, Schum.) 
Mangilia (err. cor.) Phil. Handb. Conch. p. 38. 
A473, MANGELIA PACUTICOSTATA, Var. SUBANGULATA. 
M. t. rubro-fusca, subturrita ; apice haud acuta, anfr. i. 
levibus 3 anfr. normalibus iv. +...... , excurvatis ; costis Xx. 
acutioribus, subundulatis, ad basin continws, lineis ‘pler Uumague 
spiram oblique ascendentibus, ad perupheriam subangulatis ; 
