42 [Febmaiy, 



in Illigcr'H l\[;iga.zin (1808). Upon this follows a descriptive notice of 

 the characters of tlie imago, a few words about the larvjc, pupa? and 

 galls, aud a list of the species previously described. The number of 

 joints of the antennse is stated thus: — " illorum rumiero pro sexu 

 vario " (12 in feminis, 24 in masculis, Meigeu), which proves that 

 Latreille, in this case, relied on Meigen's " Klassification " (1804). 



This passage of Latreille (1809) became the starting ]joint of the 

 generic concept, Cecidomi/ia, Meigen-Latueille, which, with the im- 

 provement in its definition introduced by Meigen in his principal 

 work of 1818, has prevailed in Dipterology up to the time when 

 Rondani and Loew began to subdivide the genus. This essential fact 

 has been entirely overlooked by MM. Karsch and Riibsaaraen, or, at 

 least, their nomenclature is in entire disagreement with it. (Meigen, 

 in his work of 1818, had introduced in the definition the very useful 

 character, " first joint of the tarsi very short "). 



Rondani has maintained this concept, and, in his very first work 

 on Cecidomyia (Memoria Seconda, &c., 1840, p. 12), in the enumera- 

 tion of the genera, we find : Grenus V, Cecidomyia, Meigen-Latkeille, 

 after which Rondani goes on with his own subdivisions. Mr. Rlib- 

 saamen has not noticed this passage, and has misinterpreted Rondani 

 (in his paper of 1892, p. 324, at bottom), when he praises him for 

 having acted with perfect correctness, and for having shown respect to 

 Meigen's memory (" pietatvoll gehandelt") in restoring the genus 

 Cecidomyia in the original oneaning of Meigen, that is, as having 24 

 anteunal joints in the male and 12 in the female, and being therefore 

 a Diplosis in the sense of Loew. (The quotation from Loew's Progr., 

 1850, p. 20, adduced by Riibsaamen in the same place, p. 325, at top, 

 is correct as far only as it refers to Cecidomyia, Kond., sensu stricto, 

 in his Mem., 2^'^, pp. 13 — 15 [1840], and not to Genus V, Cccydomyia, 

 Meig., Latr., on p. 12 of the same paper). 



Thus far I have shown that Mr. Riibsaamen's new nomenclature 

 has been based upon an entire misunderstanding of Meigen's, La- 

 treille's and Rondani's publications on the subject. 



In regard to Rondani especially, it is difiicult to understand how 

 Mr. Rubsaamen has not perceived in that author's papers on Cecidomyia 

 there is not a single allusion to the concept of the principal genus 

 which he attributes to him. On the contrary, in the Stirpis Cecido- 

 myidarum r/enera revisa (Atti, &c., di Milano, vol. ii, 1861), published 

 eleven years after Loew's Monograph of 1850, the genera Cecidomyia 

 and Diplosis are characterized as usual (on p. 12) : Cecidomyia, under 

 F is mentioned as having the same number of antenual joints in both 



