90 



ECHINOIDEA. II. 



Suborder Amphisternata. 



Fam. Spatangidæ. 



It ma}- be expressly stated that by including here in the 4:family» Spatangidæ all the genera 

 mentioned in the following, viz. Acropsis, Hnniaster, Scliizastcr, Spatangtis, Echinocardijim and Bris- 

 sopsis. besides some few others, as Accste, Pcriastrr which I have taken the opportunity to discuss, I 

 do not mean to maintain that all these genera do really belong to one and the same family. It is only 

 a provisional arrangement; so long as I have not stndied more carefnlly all the recent genera of 

 Amphisternous Spatangoids, or at least so many of them as are available for me, I do not want to 

 give ni)- view of their classification. I hope to be able to do so in Part II of the Siani-Kchinoidea. 



Aéropsis nom. nov. 



The name Arropc by which Wyv. Thomson designated the curions Spatangoid described by 

 him in The Atlantic I. p. 381 was preoccupied and thus cannot be kept for the Spatangoid. It was 

 first nsed by Ivcach, thongh only as a Mannscript name, Acrope bidnis, for a crab of the genns 

 Macroplifhaluius I^atr. [Macr. pan'iniamis Latr.).' L,ater on, in 1860, it was emijloyed by Albers for a 

 pulmonate Gastropod of the Fam. Helicoidea {Aerope caffra; South Africa)^ It is thus beyond doubt 

 that the Spatangoid named Ai-'ropc in 1877 must have another name. I therefore propose the name 

 Ai'ropsis, which recalls the old familiar name so much that tliis change of name can scarcelv give 

 much trouble. 



25. Aéropsis rostrata (Wyv. Thomson). 



n. V. Figs. 8—10, 15, 20, 22. PI. XV. Fig.s. 1—2, 5, 8, 13, 19—21, 29, 37, 40, 43, 52. 



Synonym: Aerope rostrata Wyv. Thomson. 



Literature: A. M. Norman: Crustacea, Tunicata, Polyzoa, Echinodermata etc. Riology of the 

 «;Valorous» Cruise 1875. Proc. Royal Soc. 25. 1876. p. 211. — Wyv. Thomson: The Atlantic. I. 1x381. 

 Fig. 99. - A. Agassiz: - Challenger »Echinoidea. p. 192. PI. XXXIII. Figs. 6— 13, XXXIII. a. 8—12, 

 XXXIX. 23, XU. 7— 8. (Non.: PI. XXXIII. 1—5.) — Ver ri 11: Results of the Explorations made by the 

 Steamer <'Albatross^ off the Northern Coast of U.S. in 1883. (426). p. 539. 



In his description of this species Professor Agassiz points out that his specimens differ con- 

 siderably in outline, as is also ver>' well seen in the figures given on PL XXXIII of the tChallenger»- 

 Echinoidea. Nevertheless he does not regard them as different species, and in his recent work <The 

 Panamic Deep-Sea Echini» (p. 194) it is maintained that the differences in outline of the specimen(s) 

 figured on the PI. XXXIII of the Challenger »-Echinoidea are all 'compatible with differences due to 



' List of specimens of Crustacea in the British Museum. 1847, \). 37. 

 - Tryon; Structural aud systeniatic- Conchology. 1884. III. p. 18. 



