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



ferruginescenti-castaneo : tectricibvs alarum inferioribus virides- 

 centibus : rostro superiore niyro, inferiore albo. 



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



Hub. in Nova Grenada et rep. Equatoriana. 



Obs. Affinis Iridornithi anali, sed capite dorsoque snmmo purpu- 

 reis, pectore purpurasceute et ventre viridescente facile distinguenda. 



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

 which is in the ^luseum there under the name " Tanayra analis, 

 Tachudi." But having just hefore 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- 

 uigly 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 obtam 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 differences 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 porphi/rocephala . 



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. 



Li 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 {Sy7icera) 

 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 ])cdunele and tentacida are soldered together." 



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

 into a genus under the name of Assiminia, and named the S])ecies 

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

 the genus Limnea, in Fleming's ' British Animals,' p. 2/5 (1828), 

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

 Greenwich marshes, constituting a new freshwater genus, under the 

 title Assiminia Grayana. 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])aper "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," ]iublished in the 

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



27* 



