280 Transactions. — Zoohriy. 



at the bases of the spines and on the spaces between, longer than broad, 

 obtuse, somewhat compressed, constricted near the base. A few major 

 pedicellarise, scattered on the dorsal surface, and on the inter-radial surface 

 beneath, are much larger and stouter, with enlarged bases and obtuse tips. 

 Greatest diameter, 11 inches ; disk, 4 ; width of rays at base, 1'25. 

 Auckland, New Zealand. — H. Edwards. 



Coscmasterias, Verrill. 



Star-fishes with many rays, which are elongated, slender, and united 

 only at the base, without inter-radial plate beneath. Disk small. Ambu- 

 lacra broad, highly developed, suckers very numerous, in fom' rows. Spines 

 prominent, arranged in longitudinal rows on the rays. Dorsal surface with 

 large scattered pedicellariae. Madreporic plate large, irregular, often with 

 several accessory ones placed irregularly on various parts of the disk. 

 Dorsal plates (ossicles) arranged much as in Asterias. 



The excessive development of the rays and ambulacral system, com- 

 pared with the disk or central cavity, is the most characteristic featm-e of 

 this genus. The Asterias aster, Gray, probably belongs to this genus, but is 

 too imperfectly described for identification. 

 CosciNASTERiAS MURicATA, Verrill. 



Eays nine to eleven, slender tapering, rounded above, flat below owing 

 to the width of the ambulacra, narrowed at the base, five to seven times as 

 long as the radius of the disk, which is smaU. Ambulacral furrows shallow 

 and broad, with very numerous small suckers, crowded in four rows. Inter- 

 ambulacral plates thin, somewhat imbricated, connected with the lateral 

 plates by a row of small, stout ossicles, which alternate with small rounded 

 pores. Each inter- ambulacral plate usually bears a long, slender, tapering 

 spine ; these are arranged in a single close row. External to these is a row 

 of distant, longer, and stouter cylindrical spines, arising singly from the 

 connecting ossicles between the inter-ambulacral and ventral plates. The 

 latter are strong and imbricated, each usually bearing two longer and 

 stouter blunt spines, which form a crowded double row, along the sides of 

 the arm. Ossicles of the upper surface very stout, bearing strong, acute 

 spines, which are arranged in about five open rows, the median and two 

 external alone reaching the base of the ray ; those of the median row are 

 somewhat larger, and all are sm-rounded by close wreaths of minute pedicel- 

 larise. On the disk they are smaller and loosely scattered, often obtuse. The 

 major pedicellariae are numerous, scattered over the whole dorsal sm'face, and 

 between the ventral spines, and also form a row within the edge of the ambu- 

 lacral furrow. They vary considerably in size and form upon different parts. 

 Most of those on the dorsal surface are stout, oval, compressed, pointed, 

 nearly twice as long as wide, about -05 inch long, while with them are 



