286 ANGASIA. 



Interior : Anterior valve (figs. 43, 44, 45) considerably thickened 

 within, and shallowly grooved radially ; the insertion plate stout at 

 the base, acute at the edge, and furrowed both inside and out, the 

 edge consequently being roughly crenulated ; slits 5, corresponding 

 in position to the external ribs. Median valves (figs. 46, 47, 48) 

 having broad and thin insertion plates, which are smooth-edged, 

 and only very finely striated. Posterior valve (figs. 49, 50, 51) 

 having the insertion plate very short, thick, moderately sharp-edged 

 coarsely grooved within and without, and roughly crenulated on the 

 margin. When viewed from above (the valve resting upon a flat 

 surface) the teeth are not visible, and all touch the surface, there 

 being no upward wave posteriorly. 



Girdle coriaceous (or perhaps better, pithy) and almost smooth. . 



Length 13f, breadth Hi mill. 



Calapan, Island of Mindoro, Philippines, in coarse sand among 

 small stones, in 9 fms. (Cuming.) 



Chiton laqueatus SOWB., P. Z. S. 1841, p. 104. REEVE,. Conch. 

 Icon., t. 20, f. 135. 



The above description is mainly compiled from details furnished 

 by Mr. E. A. Smith of the British Museum, who also drew figures 42 

 -51 from one of the original specimens. The scale-like granules are 

 said to be represented somewhat too small on the figures. Sowerby 

 remarks that the four or five central valves in several specimens are 

 nearly covered by a dark purple color, the two last patched with 

 green, and the first nearly white, but subject to some variations. 

 Shuttle worth describes the girdle " limbus eorneus, minutissime 

 asperulus, " but Smith says it is nearly smooth in the British 

 Museum specimens, and the insertion plates are visible through it, 

 as shown in fig. 42. 



Genus XXVI. ANGASIA Carpenter, 1882. 



Angasia CPR., Table Reg. Chitons 1873 ; and in DALL, Proc. U. 

 S. Nat. Mus., 1881, p. 283, 286, 289, 290 (Jan. 20, 1882). Augasia 

 SCUDDER, Nomencl. Zool. p. 38 (typog. err). 



Valves outwardly and within like those of Chcetopleura, but the 

 eaves small ; girdle minutely scaly-pilose, and furnished with tufts 

 of hairs at the sutures. Type A. tetrica Cpr. 



I have seen no specimen of this form, which I believe to be 

 related to Craspedochiton. Carpenter writes as follows : 



