No. 7. — Contributions from the Zodlogical Laboratory of the 
Museum of Comparative Zodlogy at Harvard College, under 
the direction of E. L. Mark, No. 123. 
THE OTOCYST OF DECAPOD CRUSTACEA: ITS 
DEVELOPMENT, AND FUNCTIONS. By C. W. 
Introduction 
Part I.— Morphology . 
A. Historical Survey 
B. Observations . 
1. Material. . 
2. Methods. . OG pe ld 
3. Structure and Development 
I. Paleemonetes . 
1. 
to 
co 
Structure of the 
Otocyst 
i SEG 5 6 > 
6. Sensory Cushion 
c. Structure of 
Hairs . 
d. Formation of 
skits) 6 6 6 
ec Otoliths’.) ec 
. Innervation of the 
Otocyst 
a. Number of 
Nerve Ele- 
ments to a 
Single Bristle 
6. Peripheral Ter- 
minations 
c. Central Termi- 
nations 
d. Histology of 
the Nerve Ele- 
ments . 
- Development of 
the Otocyst. 
(In Homarus 
americanus.) 
a. 1st larval Stage 
Doda e 
C. 
Gpatday OC al 
é. 
PAGE 
180 
180 
180 
181 
182 
182 
184 
185 
186 
188 
190 
191 
VOL. XXXVI. —NO. 7 
II. Crangon 196 | III. 
PAGE 
TABLE OF CONTENTS. 
STRUCTURE, 
PRENTISS. 
PAGE 
eel Gs 
a aia Hay) 
5 1G) 
177 
iets 
178 
- 180 
PAGR PAGE 
200| IV. Carcinus 204 
200 205 
200 sit ee ore 205 
200 ae, ve 206 
201 208 
202 Soetoro lel: 
202 Oo oo. eel 
202 os 5 eel! 
203 AL tC 212 
203 OO 3 213 
203 au siecmeel 
204 5 213 
204 sHiventie 214 
Ist Zoea 214 
a ethd 2s 914 
ayel 214 
- - Megalops . 214 
- - Youngcerab 214 
