118 IOWA STUDIES IN NATURAL HISTORY 



Canal to Barbados, but that seems so highly improbable that we 

 are better justified in believing that Pseudoholetia is a natural 

 member of the Barbadian fauna. It is strange that neither the 

 "Blake", the "Hassler", nor the "Albatross", nor any other 

 collector in the West Indies, has met with the genus but the 

 reason may be that the vessels mentioned did nearly all their 

 collecting outside the 100 fms, line while the other collectors 

 have done very little dredging at any depth. The teeming area 

 between 10 and 100 fms. has scarcely been touched as yet. 



ECHINOMETRA LUCUNTER 



Echinus lucunter Linne, 1758. Sys. Nat. ed, 10, p. 665. 



Echinometra suhangularis A. Agassiz, 1872. Rev. Ech., p. 283,. 

 pi. Xa, figs, 2-4. 



Echinometra lucunter Loven, 1887. Ech. Linnaeus, p. 157. 



Of this very common species, there are 94 specimens in the 

 collection, of which 7 are bleached bare tests. Only three are 

 from Barbados, the remaining 91 being from the Pillars of Her- 

 cules and English Harbour, Antigua. The largest specimen is 

 53 mm. long, 43 mm. wide and 28 mm. high, while the smallest is 

 about 9X8X4.5. Some of the specimens from English Harbour 

 are very dark-colored, a very dark purple-drab or a violet-black. 

 They are also quite wide in proportion to the length and look 

 as though the ambitus were a circle, but examination shows the 

 width is always 1.5-3 mm. less than the length. The Barbados 

 specimens are of two types of coloration : 2 are fawn-color be- 

 coming purplish-red at spine tips, while the third is dark olive, 

 the primaries with purple tips. 



At English Harbour, specimens taken from the rocks near the 

 entrance show the effects of the heavy surf in which they spend 

 so much of their lives. The primary spines are nearly all dis- 

 torted or regenerating at the tip. In the Narrative (p. 189), 

 Professor Nutting describes the conditions under which the 

 Echinometras flourish at Antigua. In speaking of their occur- 

 rence at Barbados (p. 83) he says that E. viridis is a "very com- 

 mon form" and that E. lucunter is "less common". As there 

 are no specimens of viridis in the collection and both Barbados 



