122 HAWAIIAN AND OTHER PACIFIC ECHINI. 



Globiferous pedicellariae not as above. 

 Genital pores 4. 



Globiferous pedicellariae small with short tubular blade and 1 tooth on 



each side of terminal opening wyviUii. 



Globiferous pedicellariae with stout tubular blade and 1-3 slender teeth 



on each side of terminal opening giganteus. 



Genital pores 3. 



Globiferous pedicellariae with the large terminal opening surrounded by 



about 7 long slender teeth naresianus. 



Globiferous pedicellariae small with 2 (or 1?) teeth on each side of termi- 

 nal opening loveni. 



Urechinus clypeatus. 



Cystechinus clypeatus A. Agassiz, 1879. Proc. Amer. Acad., 14, p. 208. 



Mortensen has shown that two quite distinct species were included under 

 this name in the Challenger report. The true urechinid is the "thin-plated" 

 form from the southern Atlantic. The "thick-plated" form from the China 

 Sea is not identifiable but is probably one of the Pourtalesiidae. 



Urechinus drygalskii. 



Mortensen, 1905. Vid. Med. f. 1905, p. 241. 



This species is known only from the holotype taken in the Antarctic deep 

 sea by the German South Polar Expedition, 1901-03. 



Urechinus reticulatus. 



H. L. Clark, 1913. Bull. Amer. Mus. Nat. Hist., 32, p. 224. 



This species is also known only from the holotype, which was taken by the 

 Albatross in 879 fms. off Lower California. 



Urechinus wyvillii. 



Cystechinus wyvillii A. Agassiz, 1879. Proc. Amer. Acad., 14, p. 20S. 

 Urechinus wyvillii Mortensen, 1907. Ingolf Ech., pt. 2, p. 50. 



This is an Antarctic species taken by the Challenger at great depths rang- 

 ing from 1375 to 2160 fms. 



Urechinus giganteus. 



A. Agassiz, 1898. Bull. M. C. Z., 32, p. 79. 



This is the largest species of the genus and was taken by the Albatross 

 in the Gulf of California in 995 fms. 



