ing pseudopodia* ; and 4, Radiolaria with siliceous, highly forami 



ated test as regards the more typical forms. 



Remains of Foraminifera, all belonging to living species, were 



detected some years ago in the leda clay formation (immediately 

 above the true drift deposits/ see Part Y.) by 

 Sir J. W. Dawson in the vicinity of Montreal, 

 and at Beauport, near Quebec. The most com- 

 mon form is the Polystomella (or Nonionina?), 

 shown at B in the following highly magnified 

 figure. Another, but much less common form, 

 from Beauport, observed by the writer in some 



B Polystsmeiia (or NO- sandy matter in the interior of a fossil balanus, is 



nionina - ?) umbilicata. , T . . . c m i ' v 



A Textuiaria (varia- s ^ ewn at A. It is a species of Textularia : a living 



mis?). genus, dating from the Carboniferous epoch. 



In addition to these essentially microscopic forms found in our 

 post-cainozoic deposits, some comparatively gigantic types, referred 

 rightly or wrongly to the foraminifera, have been discovered in our 

 Archaean and Palaeozoic (Cambrian and Lower Silurian) rocks. 

 These comprise, chiefly, the Eozwn of Dawson, the Archceocyathus 

 and some related forms together with the Pasceolus of Billings, and 

 the Receptaculites of Ferdinand Roeiner. The true nature of these 

 fossil forms, however, is exceedingly obscure. The Eozoon is 

 regarded by Mbbius, King, and other high authorities, as entirely of 

 inorganic origin, notwithstanding the able memoirs of Dawson and 

 Carpenter in defence of its assumed foraminiferous character. It 

 occurs, with us, in the crystalline Lauren tian strata of North 



The Foraminifera may be sub-divided, practically, as in the following synopsis : 

 GROUP I. Imperforata : Body -covering or shell with single external opening for passage of 

 pseudopodia. 



1. Chitonosa : With chitonous (or indistinct) body-covering : 



Fam. 1. Gromidce (e.g., Gromia, Lieberkiihnia). 

 2. Arenacea : With body-covering made up of agglutinated sand-grains, &c. 



Fam. 2. Lituolidce (e.g., Lituola, Saccamina). 

 3. Porcellanea : With calcareous, non-foraminated, porcelain -like shell. 



Fam. 3. Miliolidce (e.g., Cornuspira, Miliola. &c.). 

 GROUP II. Perforate/, : with distinctly foraminated shell : 



4. Vitrea : Shell more or less distinctly hyaline ; calcareous ; foraminated : 



Fain. 4. Lagenidce : Shell with very minnte foramina (e.g., Lagena, Cristel- 

 laria, &c.). 



Fam. 5. Globigerinidce : foramina* comparatively large ; shell thin (e.g., 



Textilaria, Globigerina, &c.). 

 Fam. 6. Nummulinidce : foramina comparatively large; shell solid (e.g., 



Nummulina, Fusulina, &c.). 



