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BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



VOLUME 1 



believed latterly that it may be the same as his Caryometra atlantidis described in 1940. 

 Hartlaub also described Antedon arcana from a Blake specimen of unknown locality in 

 the Caribbean region. Mr. Clark subsequently believed this to be a synonym of 

 Adelometra tenuipes although in his Ingolj report he listed them separately. 



In 1934 Mr. Clark described and figured Psathyrometra acuta from off Puerto Rico, 

 which he has since recognized as another synonym of tenuipes. 



The genus Caryometra, with type species Adelometra tenuipes A. H. Clark, 1908, 

 was diagnosed in 1936. In the following year Mr. Clark added to it a new species, 

 C. robusta, from off the Maldive Islands collected by the John Murray Expedition 

 which I [A.M.C.] am now referring to the subfamily Perometrinae. 



[Austin H. Clark] In 1939 Dr. Hubert Lyman Clark requested me to describe 

 the species of the family Antedonidae that had been collected in the waters about 

 Cuba by the Atlantis of the Woods Hole Oceanographic Institution in 1938. In this 

 collection I was surprised to find no less than five apparently quite distinct new spe- 

 cies of the genus Caryometra monilicirra, atlantidis, spinosa, lisa, and alope. The 

 only species previously known from the Caribbean region (tenuipes) was not repre- 

 sented. On reviewing this genus I found that Hartlaub's Antedon arcana and my 

 Psathyrometra acuta were synonyms of tenuipes, and also that Hartlaub's Antedon 

 liathra was probably the same as Caryometra atlantidis. My report on this collection 

 was published in Cuba in 1940. 



Unfortunately, the specimens collected by the Atlantis had been dried, and the 

 few representatives of each species sent to Washington by Dr. Clark were much bro- 

 ken in transit. Most of the records for Adelometra alope and A. atlantidis and one 

 of the two for A. spinosa are based on identifications made by Dr. Clark after receipt 

 of the descriptions of the new species and return of the specimens submitted. 



TABLE 14. Main numerical characters of the species of Caryometra 



[NOTE BY A.M.C.] Finally in 1954, Mr. Austin Clark included the species of 

 Caryometra in his fauna list of the echinoderms of the Gulf of Mexico. It can be 

 seen from the table that the first five species tend to form a descending series of size 

 and numbers of segments, though with some values out of phase, such as the rela- 

 tively smaller number of cirrus segments in lisa at a size of about 45 mm. arm length. 

 The proportions of the cirrus segments probably vary to some extent with size, the 

 smaller specimens having relatively longer and narrower segments. It is also likely 

 that there is some variation in the elaboration of the spicules from the distal pin- 



