BIOLOGICAL, SURVEY OF WOODS HOLE AND VICINITY. 
723 
Crepidula convexa — Continued, 
of the genus which are present locally, the 
former being almost exclusively a littoral or ad- 
littoral form. It is commonly found upon the 
shells of Littorina litorea and Ilyanassa obsoleta, 
when occupied by Pagurus longicarpus; occa- 
sionally upon the shells of the living mollusks, 
or even upon eelgrass. 
Fish Hawk stations: 7524 bis (? 1 living), 7525 
bis (? 1 living), 7532 (1), 7546 bis (? living), 
7547 bis (? living), 7552 bis (1 shell), 7560 (1), 
7584 (2, 1 living), 762r (? few shells), 7630 (1 
living), 7632 (1 living), 7654 (1 shell), 7668 (1 
living), 7672 (3 living), 7725 (2 living), 7782 
(1 shell and 1 living). 
Phalarope and Blue Wing stations: 6 (1 living), 
9 (1), 17 (1 living), 19 (common on Tritia and 
Littorina), 20 (1 living on Tritia ), 34 (1 frag- 
ment), 50 (1 on Littorina), 52 (several living), 
53 (1), 62 (several living), 68 (2 living on Tritia) 
71 (1 living), 72 (1 with eggs), 78 (1 on Anachis 
shell), 79 (on Littorina), 80 (many shells), 81 
(1), 82 (1 living), 83 (1 living), 93 (1 living), 
94, 95, 98, 104, 107 (1 shell), 109, 122 (1 living), 
126 (1 living), 130 (1 shell), 134, 136, 138, 140 
(few shells), 145 (few living), 147 (2 living), 
150 (1 shell), 152 (1 living), 154 (several shells), 
157, 158 (2), 163 (1 small living), 164 (several 
living), 165 (several living and shells), 166 (1 
shell), 167 (1 living). 
Breeds from July 1 to September 1 ; males smaller 
than females and motile. — Conklin. “A de- 
pressed varie.ty ( glauca ) is found, chiefly on 
broad and nearly flat surfaces.” — Verrill. 
Crepidula plana Say. [Chart 185.] 
Gould, 1870, p. 272; Verrill and Smith, 1873, p. 
650, 355, etc. {Crepidula plana and Crepidula 
unguiformis); Dali, 1889, p. 152; Conklin, 
1897, p. 12; Thompson, 1899, p. 582. 
Abundant and of general distribution throughout 
the shallower and deeper waters of the region. 
Distribution coextensive with that of the hosts. 
Most frequently found inside shells occupied 
by hermit crabs; small specimens (perhaps a 
“dwarf variety” — Conklin) being associated 
with Pagurus longicarpus, larger ones with 
P. pollicaris and P. acadianus; also occurring 
on the outside of oysters, on Limulus and in 
other places. Dredged by the Survey in 2 to 
25 fathoms, on every variety of bottom. 
Fish Hawk stations: 7521 (few shells), 7521 bis 
(few shells), 7523 (few shells), 7523 bis, 7524 
(few shells), 7525 (few shells), 7525 bis, 7526 
(several), 7527 (1), 7530 (few), 7530 bis (few 
living), 7531 (few), 7532 (few), 7534 (many in 
Crepidula plana — Continued. 
Polynices shells, 1 in Littorina shell), 7537 
(many), 7538 (many), 7540 (1 in Ilyanassa 
shell), 7541 (few shells), 7541 bis (few shells), 
7542 (many), 7543, 7543 bis (many living), 7544 
(few), 7545 bis (1 small), 7546 bis (living), 7547 
(few shells), 7547 bis (living), 7548 (few shells), 
7549 (few shells), 7549 bis (many living in 
Polynices heros shells), 7550 (many), 7551 (many 
in Polynices shells), 7551 bis (few living and 
shells), 7552 (few shells), 7552 bis (few shells), 
7554 (many small in Polynices shells), 7536 (few 
in Polynices), 7556 bis (numerous shells), 7557 
(many in and on shellsof Polynices heros and P. 
duplicata), 7558 (few shells), 7559 (many in and 
on shells of P. heros and P. duplicata), 7561 
(many in and on shellsof P. heros and P. dupli- 
cata), 7563 (many: some on the outside of 
shells), 7563 bis (fewshells), 7564 (several; some 
on the outside of shells), 7564 bis (living and 
shells), 7565 (1 shell), 7565 bis (several shells), 
7566 (few shells), 7567 (few shells), 7568 (few 
shells), 7569 (few shells), 7570, 7571 (x shell), 
7572 (few shells), 7574 (few), 7576 (in Poly- 
nices shells), 7577 (few), 7578 (many living 
in Polynices shells), 7579 (many living in 
Polynices shells), 7581 (1), 7582 (several), 
7583 (few shells), 7584 (few), 7585 (few 
shells), 7587 (1 shell), 7592 (many in Poly- 
nices shells), 7595 (few), 7597 (few shells), 
7398 (few shells), 7602 (1 shell), 7609 (in Poly- 
nices shells), 7612 (1 small), 7613 (r shell), 
7614 (fewshells), 7615 (fewshells), 7617 (many 
living), 7620 (few shells), 7621 (many living 
and shells), 7624 (few shells), 7625 (few shells), 
7626 (few shells), 7627 (few shells), 7628 (many 
shells), 7629 (few shells), 7630 (many small 
shells), 7631 (common living), 7632 (many 
living and shells), 7633 (few), 7634 (several), 
7635 (many shells), 7636 (1 living), 7638 (sev- 
eral living), 7639 (fewshells), 7640 (few living), 
7641 (few living), 7643 (r shell), 7644 (few 
shells), 7645 (t shell), 7647 (1 shell), 7648 (many 
living and shells), 7651 (few shells), 7632 
(few), 7653, 7655 (1 shell), 7656 (few shells), 
7657 (few shells), 7638, 7639 (few shells), 7660 
(many living), 7661 (many living and shells), 
7663 (many shells), 7664 (many living), 7665 
(several living), 7668 (few shells), 7672 (sev- 
eral living and shells), 7674 (few shells), 7675 
(few shells), 7676 (living in Polynices shells), 
7677 (living in Polynices shells), 7678 (many liv- 
ing in Polynices, also shells), 7679 (living and 
many shells), 7680 (very abundant), 7681 (liv- 
ing abundant), 7683 (few living), 7695 (1 shell), 
