110 IOWA STUDIES IN NATURAL HISTORY 



before all the differences between the two species can be clearly 

 set forth. 



COELOPLEURUS FLORIDANUS 



A. Agassiz, 1872. Rev. Ech., p. 102. 1883, "Blake" Ech., pi. 

 VII. 



The specimens of this fine sea-urchin are all from the deeper 

 water off southwestern Barbados. All are very young, the tests 

 measuring only &-13 mm. in horizontal diameter. The spines 

 are generally more or less badly broken but when these are intact 

 they are usually 4-4.5 times the test diameter. The only diver- 

 sity these individuals show is in the degree of brightness of their 

 coloration. Some have no trace of blue or lavender abactinally 

 while others, larger ones, have it quite well marked. The 7 speci- 

 mens were taken at the following stations : 



Station 7. May 16, 1918. W. by N. Pelican Island, 2 miles, 

 80 fms. Rocky bottom. Tangles. 1 specimen. 



Station 19. May 18, 1918. I1/2 miles west of Needham Point, 

 80 fms. Rocky bottom. Dredge. 1 specimen. 



Station 26. May 20, 1918. Due W. of Pelican Island, 75 fms. 

 Rough, stony bottom. Dredge. 1 specimen. 



Station 34. May 23, 1918. S. E. of Hastings, 2 miles off 

 shore, 80-90 fms. Rocky bottom. Tangles. 1 specimen. 



Station 36. May 23, 1918. S. W. of Carlisle Bay, 2 miles off 

 shore, 80-90 fms. Rocky bottom. Tangles. 2 specimens. 



Station 88. June 7, 1918. Lazaretto E. by N. 1/0 N., Pelican 

 Island S, E. Depth (?). Fine sandy bottom. Dredge. 

 1 specimen. 



LYTECHINUS CALLIPEPLUS 



H. L. Clark, 1912. Mem. M. C. Z., 34, p. 251 ; pi. 96, figs. 4-6. 

 The rediscovery of this interesting little species by Professor 

 Nutting's party is of real importance and the five specimens ob- 

 tained throw a great deal of light on the specific characters, for 

 the holotype was only 8.5 mm. in diameter and the largest known 

 specimen was only 11.5 mm., while the largest in the present 

 series is 20 mm. and another is 17. These larger specimens show 



