ZOOLOGY AND BOTANY^ MICROSCOPY, ETC. 375 



Eudiocrinus.* — Professor E. Perrier signalizes the presence of Mr. 

 Herbert Carpenter's new genus Eudiocrinus (so called from its known 

 four species having been found in the Pacific Ocean) in the Atlantic ; 

 and he proposes to call the new form (discovered by the ' Travailleur ') 

 E. atlanticus. The five arms, which alone are possessed by this genus, 

 are here greatly elongated, and only diminish slowly in diameter. 

 It is distinguished by the number and size of the saccular organs ; it 

 would not seem to be able to attach itself by its cirri, as do most of 

 its allies, but to lie with arms and cirri extended on the slime of the 

 ocean, where it fears neither waves nor ciu-rents. Eudiocrinus is not 

 a primitive, but a modified Comatulid, and the author takes again 

 the opportunity of pointing out that the simplest forms of all types 

 appear to be capable of forming colonies by gemmation ; and that 

 the abyssal fauna is, in great part, made up of forms descended from 

 littoral and shallow regions. The conditions of existence becoming 

 more and more constant, or even altogether uniform, species from very 

 different stations have, when a certain zone is passed, been able to 

 distribute themselves largely, and so to give to the deep-sea fauna a 

 monotony remarkable as compared with what obtains in the neigh- 

 bourhood of the shore. 



Arctic and Antarctic Crinoids.f — Prof. F. Jeffrey Bell describes 

 a specimen of Antedon from the Straits of Magellan which he is 

 unable to distinguish as more than a variety from the very well 

 known Arctic form A. eschricliti. After pointing out such differences 

 as there are, he confesses his inability to believe that the Magellan 

 variety and the northern form could ever have had an ancestor of the 

 species A. escliricJiti. He concludes that a case of this kind forces on 

 the mind the difference between the objective and the subjective view 

 of what constitutes a species, or in other words, the differences between 

 a Linnean and a genetic conception of specific relationship. He 

 " would not like to be thought to have failed to recognize that in the 

 discrimination of the homogenetic and the homoplastic factors of 

 species, we have at present no criterion other than what even a friendly 

 critic might call our ignorance. Chorology and palaeontology will 

 have to do for species what comparison and embryology are doing 

 for organs." 



Classification of the Comatulse.J — P- Herbert Carpenter here 

 discusses and criticizes parts of Prof. Jeffrey Bell's ' Attempt to 

 apply a Method of Formulation to the Species of the Comatulidse.' § 

 After allowing the necessity of some method of formulation, he dis- 

 cusses especially the formulas given for those species which he has 

 himself described. Confusion has arisen from preceding writers, 

 himself included, having not sufficiently recognized the different 



* Comptes Kendus, xcvi. (1883) pp. 725-8. 



t Proc- Zool. Soc, 1882, pp. 650-2. 



X Ibid., pp. 731-4. 



§ See this Journal, ii. (1882) p. 791. 



