Dr. J. E. Gray on the genus Assiminia. 419 



ferruginescenti-castaneo : tectricibus alarum inferiorihus virides- 

 centibus : rostro superiore nigro^ inferiore albo. 



Long, tota 5*6, alse 3*0, caudse 2*2. 



Hab. in Nova Grenada et rep. Equatoriana. 



Obs. Affinis Iridornithi anally sed capite dorsoque summo purpu- 

 reis, pectore purpurascente et ventre viridescente facile distinguenda. 



When at Berlin in 1854 I first noticed a specimen of this Tanager, 

 which is in the Museum there under the name " Tanagra analis, 

 Tschudi." But having just before that had the opportunity of ex- 

 amining type specimens of the latter bird in the collections of 

 Brussels and Bremen, I saw at once that the present was to all 

 appearance a distinct although closely allied species, and accord- 

 ingly assigned to it a new name in my MS. At Neufchatel I 

 again saw Tschudi's analis (the types described in the Fauna Peruana 

 being contained in the Museum at that place), and I was also so 

 fortunate as to obtain by exchange, through the courtesy of M. Cou- 

 lon, the Directeur of the Museum there, a duplicate example of 

 that species. Upon comparing this with a skin lately received by 

 Mr. Gould along with other birds from the neighbourhood of Quito, 

 I find the same diiferences as I had previously noted in the Berlin 

 Museum specimen; and, fortified by a second example, no longer 

 hesitate to introduce the bird as new to science under the title of 

 Iridornis porphyrocephala. 



February 12, 1856.— Dr. Gray, F.R.S., in the Chair. 



On the Genus Assiminia (Leach). 

 By Dr. J. E. Gray, F.R.S., P.B.S. etc. 



In a list of some species of British shells at the end of an arrange- 

 ment of MoUusca in the * London Medical Repository' for 1821 (vol.xv. 

 p. 239), I noticed a new moUusk under the name of ^'Nerita (Sgncera) 

 hepatica, n. s. The animal of this shell differs from all others of this 

 order by the eyes appearing to be at the end of the tentacula, but I 

 believe that they are placed on a peduncle as long as the tentacula, 

 and the peduncle and tentacula are soldered together." 



Dr. Leach, when he examined the animal of this shell, formed it 

 into a genus under the name of Assiminia, and named the species 

 after myself as A. Gray ana, described under this name at the end of 

 the genus Limnea, in Fleming's * British Animals,' p. 275 (1828), 

 who observes, " Dr. Leach sent me several years ago a shell from 

 Greenwich marshes, constituting a new freshwater genus, under the 

 title Assiminia Gray ana. The lip is thickened on the pillar and re- 

 flected over the cavity, but is destitute of the oblique fold, and the 

 lip does not extend over the body whorl. The colour is brown ; 

 whorls six in number, conical, regularly increasing in size, glossy, 

 with minute lines of growth. Length about -^^ths of an inch." 



In my paper "On the Difficulty of distinguishing certain genera of 

 Testaceous Mollusca by their Shells alone, and on the Anomalies in 

 regard to Habitation observed in certain species," published in the 

 * Philosophical Transactions ' for 1835, p. 301, I observe: "About 



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