500 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 53. 



sertion plates short, entire; girdle with crowded arenaceous, short 

 spinules, interspersed near the valve margins with sparse longer 

 white spines, the body of the girdle partaking of the colors of the 

 shell, with a silvery reflection in certain aspects; extreme edge of 

 the eaves finely striated in accordance with the exterior sculpture; 

 interior whitish, the jugal sinus obscure, the sutural laminae narrow, 

 arcuate, widely separated ; a conspicuous median excavation bordered 

 behind by two winglike, radially grooved, narrow callosities on the 

 internal face of the valve under the central area of the posterior 

 valve. Length of valves, IT ; width, 8 ; height, 3 mm. 



fl abitat. —Sa.ntii Barbara Channel in 20 to 40 fathoms; F. A. 

 Woodworth. Cat. No. 274120, U.S.N.M. 



This has som.ewhat the aspect of the European Chiton asellus 

 Speiigler, which, however, has a differently clothed girdle and is 

 proportionately wider and shorter. 



It has been known for some years under the above manuscript 

 name, having been by inadvertence omitted from a paper in which 

 other chitons were described in 1902. 



LEPIDOPLEURUS (LEPTOCmTON) LYCURGUS, new species. 



Chiton minute, white, with touches of brown on either side of the 

 jugal area; dorsum rather angular with flattened sides; anterior 

 valve less than semicircular, its edge excavated behind, simple; pos- 

 terior valve axially longer, with a prominent smooth subcentral mucro 

 over a conca^ e posterior slope ; central area axially grooved, minutely 

 granulose; posterior area with radial granulose very minute sculp- 

 ture; intermediate valves with no marked jugal area, that and the 

 pleural tracts with oblique minute reticulations; lateral areas dis- 

 tinct, radially minutely striate-punctate, with some obscure con- 

 centric undulations distally; girdle spiculose with minute white 

 spinules of uneven length; interior whitish. Length of valves, 4.5; 

 width, 3 ; height, 1 mm. 



Habitat. — Catalina Island, California, between tides, collected by 

 W. H. Dall. Cat. No. 274119, U.S.N.M. 



LEPIDOPLEURUS (LEPTOCHITON) OLDROYDI, new species. 



Chiton white, with a blackish spot on either side of the jugal area, 

 strongly sculptured; back moderately arcuate, anterior valve semi- 

 circular, sculptured with irregularly disposed small prominent round 

 pustules; posterior valve with subcentral prominent mucro, the cen- 

 tral area granulose, the periphery pustulose; intermediate valves 

 with axially puncto-striate jugal area, lateral areas prominent by 

 reason of the conspicuous pustules which are relatively large for the 

 size of the animal; the pleural tracts coarsely axially grooved, the 

 grooves more or less distinctly punctate ; girdle with crowded minute 

 spines of equal length, giving an arenaceous effect ; interior whitish, 



