SHALLOW- WATER STARFISHES 



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MEASUREMENTS. 



Radii 



This species ranges from south of San Francisco to Puget Sound 

 and northward to Departure Bay, B. C. In the Museum of Comp. 

 Zoology at Cambridge, Mass., I have studied a good series from off 

 San Francisco (No. 1304) ; Crescent City, CaHf. (No. 1303) ; Gulf 

 of Georgia, A. Agassiz (No. 1301) ; Monterey Bay (No. 1820, see 

 figs.); off Santa Cruz I., Calif. (No. 1821). It appears to be 

 common in shallow water on the Calif ornian coast. Very few 

 authentic localities have been recorded hitherto, except that given by 

 Dr. Stimpson (Bay of San Francisco). A single large specimen 

 has been sent to me from Departure Bay, B. C. (coll. H. C. Young, 

 Geological Survey of Canada). 



PISASTER CAPITATUS (Stimpson). 

 Plate XXXVI, figures 3, 4 (tjT)e) ; plate lvi, figure 4. 

 Asterias capitata Stimpson, Proc. Boston Soc. Nat. Hist, viii, p. 264, 1862. 

 Verrill, Trans. Conn. Acad. Sci., i, p. 327, 1867. ? Perrier, Arch. Zool. 

 Exper., rv, p. 335, 1875 (six-rayed specimen, no descr.). 



Dr. Stimpson described this species as follows: 



" Rays five, not contracted at base ; disc large. Proportion of 

 diameters, i : 4.5. Ambulacral pores rather narrow, in four regular 

 rows. Ambulacral [adambulacral] spines in one regular row, linear, 

 compressed, and blunt. Ventral spines as long as the ambulacrals, 

 capitate, with bluntly-rounded heads, elegantly striated on the con- 

 vex inner face and tip, and with a median sulcus on the outer side. 

 They are arranged in four rows, those of the outer row being largest ; 

 and there are some minor pedicellarise on the outer sides of the 

 spines in all of the rows. The dorsal spines are not very numerous, 

 but are for the most part large, their regularly globular and beauti- 

 fully striated or radiated heads being about eight-hundredths of an 

 inch in diameter, and larger than those of the ventral spines. They 

 are arranged without order, standing about one-seventh of an inch 

 apart; but five or six longitudinal rows may be obscurely traced, 

 the marginal row being most distinct, containing eighteen or twenty 



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