THE ECHINODERMS OF THE WOODS HOLE REGION. 
553 
Remarks . — This is the common starfish of the Woods Hole region. It occurs abundantly in the 
harbor, in Vineyard Sound, and in Buzzards Bay. It was originally described from the shoals of 
Nantucket, but we did not find any off Sankaty Head or Crab Ledge. It is most common near low- 
water mark, but occurs down to 18 or 20 fathoms. The habits have been observed and described so 
well by Mead (’99) that any account of them here would be superfluous. The larval stages and 
development of this species have been described by Agassiz (’77), but curiously enough little has been 
done on the embryology during the past twenty-five years. The young stars occur in great abundance 
on the eelgrass in the Eel Pond at Woods Hole during August. The great variety of color in the 
adults has yet to be explained; it is apparently not associated with age or sex, nor has its correlation 
with the environment been proved. 
2. Asterias vulgaris Verrill. Northern starfish. (PI. 1, figs. 3, 4; pi. 4, figs. 16, 17.) 
Aster ias rubcns Gould, 1841. 
Asteracanthion rubcns Jlesor, 1848. 
Asleracantlnon violaccus Stimpson, 1853. 
Asteracanthion rubens Stimpson, 1853. 
Asteracanthion paUiclus A. Agassiz, 1863. No description. 
Asterias vulgaris Packard, 18G3. No description. 
Asterias vulgaris Verrill, 1866 et seq. 
Asterias stimpsoni Verrill, 1866 (pars.). 
Asterias pallida Goto, 1898. 
Description . — Rays normally 5, rarely 4 or 6. R=75 to 150 mm. or even more, specimens 425 mm. 
in diameter being reported from Nova Scotia, r=9 to 30 mm., R— 4.5 to 8.5 r. Breadth of ray near 
base, 15 to 30 mm., R=3.5 to 5 br. Rays more or less flattened, the. sides somewhat vertical, tapering 
to a more or less acuminate point. Disk usually rather large, sometimes considerably arched. Inter- 
brachial arcs somewhat acute. Abactinal area covered by a network of narrow plates with large 
meshes, not forming a very firm skeleton. Almost always there is a median longitudinal series on the 
arm, with large papular areas (sometimes 4 or 5 mm. across) on each side. All the plates bear blunt 
spines 1 or 2 mm. high, usually singly but occasionally 2 or 3 together. The spines are rough or 
minutely thorny at the tip, and are encircled by a more or less complete wreath of pedicellarise, 
which are remarkably blunt. Pedicellarise scattered over abactinal surface much larger and quite 
acute. Along side of ray a very well-marked lateral series of spines, below which is a longitudinally 
extended area of greater or less extent quite free from spines, but with numerous pedicellarise. The 
lateral series varies greatly in position, in some specimens being quite near the abactinal surface, while 
in others it may be scarcely visible when seen from above. It, is made up of plates bearing 2 spines, 
side bv side, so that there is apparently a single line of spines. In older specimens, however, there 
is often a third spine beneath the distal one. of each pair, and frequently a fourth spine occurs above 
or beside the proximal one. Well down on the actinal surface of the ray is another series of spines, the 
largest and most prominent of all. These are usually over 2 mm. in length and are often 3 or 4 mm. long; 
they are very blunt, even square cut or clavate, in some specimens deeply so. Three spines form 
an oblique row on each plate, the most distal being nearest to the ambulacral furrow. Although 
these spines bear pedicellarise, often in great numbers, they are not so nearly wreathed by them 
as are the abactinal spines. Adambulacral plates with 1 or 2 (usually 2) rather long (2 to 4 mm.) 
somewhat flattened slender spines, pointed, square cut or clavate at the end, most of which carry 
from 1 to 6 long, slender and very acute pedicellarise (fig. 17). A few small pedicellarise occur on the 
adambulacral plates within the furrow. The acute pedicellarise on the adambulacral spines are 
present even in very small individuals (15 to 20 mm. in diameter). Adambulacral plates are more 
numerous in this species than in any of the other forms of Asterias occurring at Woods Hole. In a 
specimen with R=18 mm. there are 65 or more plates on each side of the furrow; in another with 
R=24 mm. there are about 75; in another with R=37 there are only about 110; in another with 
R=107 there are not less than 170. Oral spines not peculiar. Papular areas generally large, with 3 or 
more papulae in each group. Madrepore plate of moderate size, 2 to 5 mm. in diameter, with 
numerous narrow furrows, and not surrounded by any special circle of spines. Tube feet quadriserial, 
crowded. Color in life very variable; the most common shades are yellow and purple, but cream- 
colored, yellow-brown, brown, orange, pink, and even bright red individuals occur. Spines generally 
light, ami madrepore plate light yellowish. 
Range . — Labrador to Cape Hatteras; but south of the Woods Hole region rarely seen in shallow 
water; low water to 358 fathoms. 
Remarks . — Although less common than A. f orbed, this species occurs in abundance in many places 
near Woods Hole. In the harbor it is occasionally found with A. forbesi, and specimens have been 
