346 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



Arbacia spatuligera. 



Echinus (Agarites) spatuliger A. Valenciennes, 1846. Voy. Venus Zoophytes, pi. 5, 



fig. 2. 

 Arbacia spatuligera A. Agassiz, 1872. Rev. Ech., pt. 1, p. 93. 



Plate 10, figure 2. 



This characteristic species ranges from Guayaquil to southern Chile. Although 

 not so large as Tetrapygus niger, its spines are so much longer (40-45 mm.) that 

 adults (65-70 mm. in diameter) cover a greater area and look fully as large. 

 Dr. Coker met with spatuligera at San Lorenzo Island near Callao, and in the Bay 

 of Sechura, about half way between Bayovar and Matacabella, in 5-6 fathoms. 

 There are no notes to show the character of the bottom or the appearance or hab- 

 its of the living animal. 



Podophora pedifera- 



Echinus pedifer H. D. de Blainville, 1825. Diet. Sci. Nat., 37, p. 97. 

 Podophora pedifera L. Agassiz et E. Desor, 1846. Ann. Sci. Nat., 6, p. 374. 



Plate 11, figure 2. 



This remarkable sea-urchin has long been known from the southern Pacific 

 islands and was found common in the Paumotus by the "Albatross" in 1899— 

 1900, " on the seaface of the reef, exposed to the full force of the surf " (A. Agas- 

 siz, 190S). Although there are specimens in the M. C. Z. collection labeled 

 " Peru," " Chile," " Callao," and " Valparaiso," no recent collectors have met 

 with Podophora on the American coast and it is highly improbable that it occurs 

 there. Yet it has seemed well to include and figure it, in the hope that some 

 Peruvian or Chilean collector may verify its occurrence or prove its absence. 



Echinometra van brunti. 



A. Agassiz, 1863. Bull. M. C. Z., 1, p. 21. 



Plate 11, figure 1. 



This well-known Panamic species has been reported from Zorritos, Peru, by 

 Verrill (1867), but it was not met with by Dr. Coker. Large specimens may be 

 75-80 mm. long, with the breadth rather more than nine-tenths as much. 



Strongylocentrotus gibbosus. 



Echinus (Toxopneustes) gibbosus L. Agassiz et E. Desor, 1846. Ann. Sci. Nat., 6, 



p. 367. 

 Strongylocentrotus gibbosus A. Agassiz, 1872. Rev. Ech., pt. 1, p. 164. 



Plate 13, figure 2. 



Among the sea-urchins of South America this species offers the most interesting 

 subjects for investigation owing to the fact that in the very great majority of 

 specimens (in museums at least) the test, aud especially the abactinal system, is 



