SHALLOW-WATER STARFISHES 69 



name, for the same type, in 1842, but did not subsequently use it. 

 This name should, therefore, take precedence of all others, whether 

 it be considered a genus or a subgenus. 

 The mode of reproduction is unknown. 



PISASTER OCHRACEUS (Brandt) A. Agassiz. 



Plate xxi, figures I, 2; plate XLIX, figures 3-3^ (pedicellarias) ; 



plate LVI, figures 3, 30 (variety). 



Aster tas ochracea BRANDT, Prod. Descr. Anim. Mertens, p. 69, 1835. 

 Asterias janthina BRANDT, op. cit., p. 69, 1835 (descr. insufficient; color var. ?). 

 Asterias ochracea STIMPSON, Journ. Boston Soc. Nat. Hist., vi, p. 87, pi. xxm, 

 fig. 2, 1867. Verrill, Trans. Conn. Acad. Sci., i, pp. 325, 326, 1867. Whit- 

 eaves, Trans. Royal Soc. Canada, iv, p. 116, 1887. A. Agassiz, North 

 Amer. Starfishes, Mem. Mus. Comp. Zool., v, p. 96, pi. xi, figs. 1-7 

 (structure), 1877 (Pisaster). H. L. Clark, op. cit., 1907, p. 67, pi. vi, 

 fig. 3 (structure). Loeb, Publ. Univ. Calif., Physiol., u, pp. 5-30, 1904 

 (hybridization). 

 Asteracanthion margaritifer MULLER and TROSCHEL, Syst., p. 20, 1842 (t. 



Bell). 



Disk rather large, strongly reticulated by the prominent ossicles 

 and spines ; rays normally five, sometimes six, stout, rapidly tapered. 

 Two Alaskan specimens, differing considerably in form, measure as 

 follows: (a) lesser radius, 36 mm.; greater radius, 120 mm.; ratio, 

 1:3.33; (b) lesser radius, 32 mm.; greater radius, 118 mm.; ratio, 

 i : 3.68. 



The dorsal spines are numerous, unequal in size, but nearly all 

 are capitate; the larger ones are short and stout, strongly capitate 

 with flattened striated tops. They are arranged in short rows form- 

 ing a conspicuously reticulated pattern, with large, deep, angular 

 papular areas between them. They usually stand so closely in the 

 rows that they nearly touch; on the disk they form a conspicuous 

 pentagon, enclosing subordinate angular groups or partial reticula- 

 tions and a central cluster. A zigzag, irregular median row is often 

 distinct on the basal part of the rays. The smaller spines are similar 

 in form but not so stout ; they are partly grouped around the larger 

 ones, and partly serve to subdivide the primary reticulations. Each 

 primary papular area usually contains several large clusters of 

 papulae. Large, short, very stout, obtuse, wedge-shaped, unguiculate, 

 dermal major pedicellariae are more or less numerous on the dorsal 

 surface, and still more so on the sides of the rays; they are rather 

 less in diameter than the adjacent spines. Those in the lateral chan- 

 nels and interradial spaces are larger and stouter than the dorsal 

 ones. Minor pedicellariae form wreaths around the bases of the 



