PEESENCE OP ETES IN SRELLS OP CEETAIN CHITONIDiE. 23 
thè Smithsonian collection at Washington and gave me some 
specimens from thè Pacific coast. 
Dr. Woodward kindly went over thè fossil Chitons with me, 
but we could not detect any traces of eyes in them. 
DESCRIPTION OF PLATES IV, V, & VI, 
Illustrating Professor H. N. Moseley’s paper “ On thè Presence 
of Eyes in thè Shells of Certain Chitonidae and on thè 
Structure of these Organs.’’ 
N.B. — All thè drawings, with thè exception of fig. 2, PI. IV, figs. 4, 5, 
and 6, PI. V, and fig. 8, PI. VI, drawn by thè author, are made from thè 
actual shells by a professional artist, Mr. W. H. Hill. 
PLATE IV. 
Eie. I. — View of a specimen of Schizochiton incisus, preserved in 
spirits, and with thè outline of thè margin of thè mantle somewhat distorted 
in consequence. a. Anterior shell, with six rows of eyes. b. Posterior shell, 
with six rows of eyes. c. Anal notch in thè posterior shell. d. One of thè 
middle shells, with two rows of eyes. e. Another of thè middle shells, which 
bears as an abnormality three rows of eyes, two on one side and oue on thè 
other. 
Eig. 2. — One of thè rows of eyes of a middle shell of Schizochiton 
incisus much further enlarged. 
Eig. 3. — A single eye from thè same specimen as thè above, stili more 
higlily magnified. b. Calcareous cornea, g. Lens, bordered by thè apertures 
of thè iris seen through thè cornea, c. Pigmented eye-capsule, seen partly 
through thè superficial layers of thè generai shell substance. 
Eig. 4. — The anterior shell of Schizochiton incisus, outer view; one 
half indicated in outliue only. On thè finished half three rows of eyes are 
seen borne ou raised ridges of thè shell. 
Eig. 5. — The same shell ; inner view. a a a, Incisurm marginalis. b b. 
The suturai lines of pores for thè passage of nerves, continued from thè 
incisurse. 
Eig. 6. — Part of a specimen of Enoplochiton niger, viewed from 
thè side. Only a part of one of thè middle shells and of thè girdle is 
