392 On the Nomenclature of the Foraminifera. 



merhouse, Thrislington Gap, Kunning Waters, Moorsley, 

 Walworth and Limekiln Banks, south of Leg's Cross. 



In Yorkshire it is very abundant, occurring, with the Milio- 

 loid variety, in myriads, in the dark-grey limestone of Noster- 

 field, and in a similar limestone at Chapel Houses, — also at 

 Gybdykes, near Mashani, Thornton Watlass, Linderick, and 

 Ilampole. 



In Ireland it has been found by Prof. W. King at TuUy- 

 connel Hill, near Artrea, co. Tyrone. 



In Germany it is very common in the Lower Zechstein of 

 Corbusen, near Konneburg, and at other places in the vicinity 

 of Gera, at Moderwitz (near Neustadt) on the Orla, at Kams- 

 dorf and Saalfeld, and in the Wetterau (^ Dyas,' p. 40). It is 

 found also in the "grauer Mergel-Zechstein," overlying the 

 Zechstein at Gera (King, Journ. Geol. Soc. Dublin, 1856). 



The discoidal or SpirilUna-like form ( Tr. incerta) is found 

 in Dm-ham in " Shell-limestone " at Tunstall Hill, and in 

 " Lower Limestone " at Langton, Thrislington Gap, Walworth, 

 and Limekiln Banks, south of Leg's Cross. 



The Nosterfield limestone, when cut and polished, shows 

 instructive sections, the matrix being almost black, while the 

 shell-substance is white. This rock is similar to the black 

 limestone of Gera and Hanau. 



This little fossil is always associated with other fossils, such 

 as Producta horrida^ Qervilia antiqua^ and IchthyoracMs an- 

 cejysy often with other Ehizopods, and as often with an obscure 

 plant-like fossil which has been named Chondrus virgatus. 

 It is always free (not attached or parasitic) ; and we do not 

 see any reason to follow Dr. Geinitz * in associating the fixed 

 vermiform fossil ( Vermilia obscura, King) with Trochammina 

 jjusilla^ 



EXPLANATION OF PLATE XIII. 



Fiff. 1. Trochammina ince)-ta. From Langton, co. Durham. Magnified 



30 diameters. 

 Figs, 2, 3, Tr. jmsilla, subdiscoidal forms. Sunderland. Magn. 15 diams. 

 Figs. 4, 5, 6. Tr. jnisilla, ordinary forms. Sunderland. Magn. 15 diams. 

 Figs. 7, 8. Tr. gorcUalis. Timstall Hill, Sunderland. Magn. lo diams. 

 Figs. 9-14. Tr. mtholoides, various forms. Svmderland. Magn. 10 diams. 

 Fig. 15. Tr. pttsilla, section. Nosterfield. Magn. 15 diams. 



* ' Dyas,' p. 39. In tlie < N. Jaiirbucli &c.' for 1864, p. 667, Herr Bolsche 

 also noticed a serpentine form, parasitic on shells &c., and intimated that 

 it and King's V. obscura may be the same as, or varieties of, the coiled 

 form. 



