394 THE VOYAGE OF H.M.S. CHALLENGER. 



Subfamily Palmipedina;, Sladen, 1888. 



Genus Palmipes, Linck. 



Palmipes, Linck, De Stellis marinis, 1733, p. '29. 



Anseropuda, Nardo, De Asteriis, Oken's Isis, 1834, p. 71G. 



Asteriscus (pars), Muller and Troschel, Monatsber. d. k. preuss. Akad. J. Wiss. Berlin, 1840, p. 104. 



This remarkable and sharply defined genus appears to be comparatively local in its 

 occurrence, although the recorded localities are widely distributed. The small number of spe- 

 cies indicates a very limited range of morphological variation, which is all the more remark- 

 able when the isolated character of the structure of the genus is taken into consideration. 



The structural peculiarities of Palmipes have led me to place the genus in a distinct 

 subfamily, in which I have included the allied genus Stegnaster. AVith these I am 

 inclined to think that Tremaster, Verrill, should also be associated ; but as I have not 

 had an opportunity of examining the structure of that form, and as no account of its 

 details has been published, nor any suggestion as to the affinities of this abnormal genus 

 thrown out by its author, I feel at present some uncertainty as to whether Tremaster 

 should be classed with the Palmipedinse or Asterininse. 



Chorology of the Genus Palmipes. 



a. Geographical distribution . — 



Atlantic : One species between the parallels of 30° and 65° N. 



Palmipes membranaceus, off the British Islands, in the English 

 Channel, off the coast of France, and in the Mediterranean and the 

 Adriatic. 



Indian Ocean : One species between the parallels of 10° and 25° N. 



Palmipes rosaceus, from the Bay of Bengal (Berlin Mus.). This 

 form also occurs of!" Japan {fide Gray). 



Pacific : Two species between the parallels of 40° N. and 5° S. 



Palmipes diaphanus, from North of Admiralty Island ; and 

 Palmipes rosaceus, from Japan, the latter extending to the Bav 

 of Bengal. 



ft. Bath y metrical range: 20 to 150 fathoms. 



Greatest range of one species : Palmipes membranacevs, 20 to 100 fathoms. 

 y. Nature of the Sea-bottom: Palmipes diaphanus lives on Coral mud. 



The nature of the ground inhabited by Pol mi pes membranaceus and Palmipes 

 rosaceus is not recorded. The want of information in the case of the compara- 

 tively common form, Palmipes membranaceus, is surprising. 



