MUSEUM OF COMPARATIVE ZOOLOGY. 



251 



hooks are found in greater or less number quite to the base of arm. Disk 

 absolutely naked in the interbrachial spaces, except along its edge above, 

 where, as well as on the high narrow radial ribs, there are minute grains, 

 about five in the length of a mm. In the space round the mouth, below, 

 there are a few scattered microscopic granules, which in an alcoholic speci- 

 men must be invisible. Five small, narrow madrcporic bodies, placed one in 

 the inner angle of each interbrachial space and close against the line of sep- 

 aration between the under and upper surfaces. Mouth and tooth-papillae 

 sharp and spiniform, arranged in an irregular clump, above which appear 

 three or four teeth, irregularly superimposed, with a striated surface and a 

 rather wide curved cutting edge. Genital openings 2.5 mm. long, situated 

 1.5 mm. inside the outer end of the radial rib. Color, chocolate-brown. 



Guadeloupe ; 20 fathoms.* A specimen in the Garden of Plants and an- 

 other, by exchange, in the Museum of Comparative Zoology. 



Astrophyton nudum sp. nov. 



Plate VI , Figs. 4-5. 



Special Marks. — Xo tentacle-scales on pores. Disk and arms quite 

 smooth ; the latter ringed with faint lines, which, magnified, are seen to be 

 rows of minute conical papilla?. One large madrcporic body. 



Description of a Specimen. — Diameter of disk 44 mm. Length of arm 

 about 375 mm., as follows : 



fork to second 10 mm. 



" " third 12 " 



Distance from first 

 " " second 



third " " fourth 16 " 



fourth " " fifth 16 " 



fifth " " sixth 17 " 



sixth " " seventh 20 " 



seventh " " eighth 20 " 



eighth " " ninth 19 " 



ninth " " tenth 22 " 



tenth " <: eleventh 20 " 



eleventh " " twelfth 20 " 



twelfth " " thirteenth 20 " 



thirteenth " " fourteenth 20 " 



fourteenth " " fifteenth 19 " 



fifteenth " " sixteenth 20 " 



sixteenth " " seventeenth 20 " 



seventeenth " " eighteenth 20 " 



eighteenth " " nineteenth 14 " 



nineteenth " " twentieth 1 7 (tip broken). 



Total, 



312 



