BIOLOGICAL SURVEY OF WOODS HOLE AND VICINITY. 



611 



Class ECHINOIDEA. 



Family STRONGYLOCENTROTID^. 



Green 



Strongylocentrotus droebachiensis (Muller). 

 sea urchin. [Chart 51.] 



Verrill and Smith, 1873, p. 716, 326, etc; Clark, 

 1904, p. 563; 1905, p. 7; Sumncr, 1910, fig. 19. 



Mouth of Vineyard Sound and off Gay Head; off 

 West Chop. Verrill. Crab Ledge, common; 

 off Sankaty Head, abundant. Clark. Com- 

 mon in Vineyard Sound, chiefly near western 

 end; appears to be absent from Buzzards Bay, 

 except near mouth; dredged on all sorts of 

 bottoms except muddy ones, chiefly at depths 

 of 10 fathoms or more. Survey. Likewise 

 taken at low water, according to Verrill, on the 

 outer, rocky shores. 



Fish Hawk stations: 7525 bis (2 very small), 7531 

 bis (i small), 7534 bis (i small, living), 7536 

 (i small), 7537 bis (i small), 7545(1 small), 7547 

 (i small), 7556 (i), 7556 bis (? i shell), 7561 

 (several), 7564 (2 large), 7582 (several), 7585 

 (i large), 7592 (i large), 7593 (i small), 7603 

 (2 small), 7604 (several very small), 7605 (2 

 small), 7606 (many small), 7607 (several small), 

 7608 (few small), 7609 (i small), 7663 (i), 7678 

 (r living), 7679 (i spine), 7680 (i large living, 

 and fragments), 7681 (many), 7695 (few spines), 

 7696 (spines and fragments), 7699 (few spines), 

 7700 (few spines), 7701 (few spines), 7702 (i 

 living), 7703 (few spines), 7704 (i spine), 7705 

 (few spines), 7706 (i small living), 7718 (i 

 small), 7719 (few spines), 7720 (i large living 

 and spines), 7723 (i), 7752 (i spine). 

 Phalarope stations: 25 (2 small), 32 (i living), 

 34 (i living), 52 (several living), 58 (spines), 

 59 (few small), 116 (i living). 

 Food: Diatoms and other small algae; also dead 

 fishes. Verrill. 



Family ARBACIID^J. 



Arbacia punctu'iata (Lamarck). Common sea 



urchin; purple sea urchin. [Chart 52.] 

 Verrill and Smith, 1873, p. 717, 326, etc.; Clark, 

 1904, p. 563; 1905, p. 8; Bumpus, 1898 b; Sum- 

 ner, 1910, fig. 18. 



In Vineyard Sound generally distributed, except 

 at western end; in Buzzards Bay chiefly con- 

 fined to inshore stations, particularly along the 

 eastern shore; living specimens dredged in 2 

 to 17 fathoms, on bottoms of sand, gravel, and 

 stones; spines and fragments more generally 

 distributed. Survey. Found, likewise, cling- 

 ing to submerged rocks along shore . Formerly 

 fairly frequent in Woods Hole Harbor, even 



\rbacia punetulaia Continued. 



within the "basin" of the local pier. In its 

 occurrence this species is scarce to abundant, 

 being subject to marked fluctuations from 

 year to year. Abundant in 1903, as dredging 

 records show; living specimens very scarce 

 during the following summer, though spines 

 and fragments were frequently taken. (It is 

 of importance to note in this connection that 

 the winter of 1903-4 was an exceptionally 

 severe one; see p. 114-116.) Dr. J. F. McClen- 

 don, who collected large numbers of A rbacia for 

 biochemical studies during the summer of 

 1908, reports that the greatest numbers were 

 taken southwest of the spar buoy lying nearest 

 to the lighthouse at Tarpaulin Cove, in water 

 of 12 to 15 fathoms depth. They were col- 

 lected most successfully by means of tangles, 

 a bucketful being sometimes taken at once. 

 Fish Hawk stations: 7521 bis (fragments and 

 spines), 7522 (many living), 7523 (several 

 living), 7523 bis (i spine), 7524 (very abun- 

 dant, living), 7526 (2), 7529 (few), 7530 

 (abundant), 7531 (i dead), 7531 bis (few frag- 

 ments), 7532 (many), 7532 bis (few spines), 

 7533 (few, many spines), 7533 bis (i small, 

 living), 7534 (numerous), 7534 bis (few spines), 

 7535 (few shells, many spines), 7535 bis (many 

 spines), 7536 bis (many spines), 7537 (many, 

 rather small), 7538, 7538 bis (spines and frag- 

 ments), 7539 (few), 7540 (few), 7541 (few), 7541 

 bis (many spines), 7542 bis (several spines), 

 7543 (fragment), 7545 (numerous, living), 7545 

 bis (fragment of shell and many spines), 7546 

 (few living), 7546 bis (spines), 7547 bis (several 

 living and fragments), 7549 (many living), 

 7549 bis (few fragments and spines), 7550 

 (fragments), 7550 bis (few spines), 7551 (few 

 living), 7551 bis (i living, several fragments), 

 7552 (few), 7552 bis (few spines), 7553 bis (few- 

 spines), 7554 (i small, dead), 7555 (numerous), 

 7556 (few), 7556 bis (many fragments and 

 spines), 7557 (i shell), 7558 (many living), 

 7559 (few living), 7561 (about two bushels), 

 7562 (few living), 7563 (many living), 7563 bis 

 (spines and fragments), 7564 (many living), 

 7564 bis (many spines), 7566 (many spines), 

 7567 (many spines), 7568 (many spines), 7569 

 bis (spines), 7571 (i), 7572 (few), 7575 (few 

 spines), 7576 (few spines), 7577 (few spines), 

 7578 (few spines), 7579 (few spines), 7580 (few 

 spines), 7597 (few spines), 7621 (i small), 7624 

 (spines), 7628 (i small), 7631 (few spines), 

 7639 (few), 7659 (spines and fragments), 7664 



