30 



NATURAL HISTORY BULLETIN 



Lytechinus variegatus 



Cidaris variegata Leeke, 1778. Add. ad Klein, p. 85. 

 Lytechinus variegatus A. Agassiz, 1863. Bull. M. C. Z., 1, p. 24. 

 Toxopneustes variegatus A. Agassiz, 1872. Eev. Ech., pt. 1, p. 298; pi. 

 IVo, figs. 5, 6. 



This, the most abundant of West Indian echini, except per- 

 haps Centrechiniis, is represented in the collection before me 

 by only 7 specimens, 3 small adults from Bahia Honda, Cuba, 

 and 4 young without locality but evidently from the Cuban 

 coast also. 



Lytechinus variegatus carolinus 



Lytechinus carolinus A. Agassiz, 1863. Bull. M. G. Z., i, p. 24. 1872, Eev. 



Ech., pi. II, figs. 5, 6 (as Toxopneustes variegatus). 

 Lytechinus variegatus carolinus H. L. Clark, 1912. Mem. M. C. Z., 34, p. 



245. 



It is rare indeed that trinomials, indicating geographical 

 subspecies, can, in the present state of our knowledge, be used 

 among echinoderms, but Lytechinus variegatus is a remarkably 

 clear case. Specimens from the northern and western sides of 

 the Gulf usually have the spines so much stouter and shorter, 

 relatively, than those of the specimens from Cuba, Jamaica and 

 eastward, and their color is so pink that they look very differ- 

 ent. But intergradations are so common and indubitable that 

 the relation is best shown by trinomials. A third form {at- 

 lanticus) is well differentiated in the Bermudas. 



The Iowa collection contains five small, poor specimens of 

 this subspecies, ranging in disk diameter from 6 to 10 mm. 

 The locality is not indicated, except that two are labelled 

 *'West Indies." They are all probably from the Tortugas. 



Tripneustes esculentus 



Cidaris esculenta Leske, 1778. Add. ad Klein, p. XVII. 



Hipponoe esculeiita A. Agassia, 1872. Rev. Ech., p. 301 ; pi. Via, figs. 1-3. 

 Tripneustes esculentus Bell, 1879. Proe. Zool. Soc. London, p. 657. 



Of the 7 specimens of this common species, only one deserves 

 any comment. It is one of the smallest specimens of this big 

 ''sea-egg" (th© West Indian native name) which I have ever 



