330 Enigmatical Names in Conchology dsc. 



apparently unknown to Jeffreys, and is unnoticed in tlie 

 4 Manual of the Mollusca ' by Woodward and Tate. In 1859 

 Ohenu's ' Manuel de Conchyliologie,' vol. i. p. 306, retains 

 " Rissoa, Fre"minville, 1814," subjoining " Rissoaria, Agassiz, 

 1846," as a synonym. Reference to the work of Agassiz, 

 ' Nomina systematica Generum Molluscon!!!^' edited by 

 Gray, Menke, and Strickland, reveals the following entries : — 



Rissoa, Frem. Bull. Soc. Phil. iv. 1814. 



Rissoaria, Frem. Bull. Soc. Phil. 1814. 

 Pursuing the quest, at p. 7 of the volume indicated we 

 find " Description des Coquilles univalves du genre Rissoa de 

 M. de Freminville ; par M. A.-G. Desmarets," followed by 

 the statement " Ce genre, dont Fe'tablissement a e"te* juge* 

 ne*cessaire par M. C. de Freminville . . . porte le nora de 

 M. Risso." Then the definition of the genus is given by 

 Anselme Gaetan Desmarets (or Desmarest), to whom, there- 

 fore, the genus should be ascribed, and not to the Baron de 

 Freminville, unless the latter did something more than suggest 

 its name. But of Rissoaria not the least trace could be 

 found in the volume cited by Agassiz. It is, perhaps, 

 nothing but an ampler emendation in advance of Rissota. 

 As a matter of curiosity, the treatment of Rissoa by Johannes 

 Gistel deserves mention. In his ' Natutgeschichte des 

 Thierreichs/ 1848, at p. x he indicates " Rissoa (Fre*m. 

 Gasterop. R. striatella, O. Fabr. ; Chiaje in Memorie V.; 

 Quoy : Isis 1834) ; Apanthausa, N." But on p. 169, after 

 Paludina achatina, be introduces the remark "Hieherdas 

 Genus Melania (dcssen Name in Hydrognoma, mihi, zu 

 andern) und Rissoa (in Anatasia, mihi, umzuwandeln." As 

 between Apanthausa and Anatasia, the latter might well 

 claim priority, since it occurs in the body of the work, while 

 Apanthausa is in -the separate pagination of the prefatory 

 portion, which, though first in arrangement, is naturally last 

 in order of production. That Apanthausa was only a slip of 

 the pen is the more likely, as in the ' Handbuch der Natur- 

 geschichte/ p. 554 (1850), he gives only Anatasia, with no 

 allusion to Apanthausa. Whatever the change intended, he 

 evidently feels that it is unnecessary for so eminent a natu- 

 ralist to vindicate or even explain its necessity. 



With regard to the Pycnogonida, I find a procedure of my 

 own inculpated (or, at least, lamented) by Dr. Loman in a 

 recent essay, which is on other accounts of much value. But 

 on the point in question he does not seem to me to adopt a 

 sound view. In 'Knowledge,' vol. xxv. no. 202 (1902), at 

 p. 187 I pointed out that Latreille in 1801 instituted the 

 genus Phoxichilus, assigning to it the single species Pycno- 



