No. 19.] ECHINODERMS OF CONNECTICUT. 83 



entire; the projecting arms are usually cut off by the dt'edge, and 

 the animal escapes; and as it has the power of restoring lost 

 arms, this is only a temporary inconvenience. The same thing 

 probably happens when a voracious fish seizes one of the arms." 



The specimens from Woods Hole were collected at extreme 

 low-water mark. In Long Island Sound the species has been 

 dredged off New Haven and at Thimble Islands at depths of 

 from three to eight fathoms, and many specimens have been 

 collected in soft mud, near low-water mark, at Noank, Connecti- 

 cut, and others at Peconic Bay, Long Island. 



The disk of mature individuals measures from 6 to ii mm. in 

 diameter. The arms are very slender and extremely flexible. 

 They are usually from twelve to sixteen times as long as the 

 diameter of the disk, and sometimes measure as much as i8o mm. 

 in length. 



In addition to the extremely long and slender arms (Plate 

 XVIII, Plate XIX, fig. i), the species may be distinguished by 

 other anatomical peculiarities. Careful examination of the jaws 

 will show the presence of four tooth-like processes, oral papillae, 

 on each edge. On the sides of each segment of the arm is a 

 series of three projecting spines, of which the middle one is 

 stouter, flatter, and less pointed than the other two. 



On the aboral side of the disk at the base of each arm is a 

 pair of narrow plates, called the radial shields. In the present 

 species these are narrow, curved, and parallel or only slightly 

 divergent, and not closely in contact. They are often partly 

 covered by the encroachment of the small scales which cover the 

 disk. The scales of the disk are without granulations or spines. 



The color of the living animal varies considerably in different 

 specimens. Some, are brown on the aboral surface of the disk, 

 with a central area of dark brown bordered by pale gray. A 

 radiating band of dark brown likewise bordered by gray extends 

 outward to each interradial margin. The radial shields are yel- 

 lowish brown, while the narrow space between them is blue. 

 There are additional symmetrically placed brown spots arranged 

 in series on the disk. The arms are brown or dull greenish, 

 often with lighter bands. The specimen from Woods Hole 

 studied by Clark was uniformly gray. 



