AraiL 1, 1870.] 



HARDWICKE'S SCIENCE-GOSSIP. 



81 



CHALK FORAMINIFERA. 



SINCE the publication of our January number, 

 with its figures of " Recent Foraminifera," we 

 have been favoured with so many letters of com- 

 mendation for having commenced in such earnest to 

 supply our microscopical readers with figures of 

 Foraminifera, that our resolution was confirmed of 

 continuing them at the earliest opportunity. Un- 

 foreseen circumstances having prevented our artist 

 making a series of drawings in continuation of what 

 we termed " Recent Foraminifera " in time for the 

 present issue, we have adopted " Chalk Foramini- 

 fera" as its temporary substitute. 



It may be known to some of our readers, that, 

 in 1S40, the celebrated M. Alcide d'Orbigny pub- 

 lished in the Memoirs of the Geological Society of 

 France, vol. iv., a very valuable paper, entitled 

 "Memoire sur les Foraminiferes de la Craie Blanche 

 du Bassin de Paris," enumerating, describing, and 

 figuring fifty-four species of Foraminifera. As this 

 Memoir was not published in any other form, it has 

 been suggested to us to reproduce the figures, in- 

 asmuch as it is exceedingly difficult for students of 

 these forms to obtain a glimpse of the figures of 

 D'Orbigny. Acting upon this suggestion, we have 

 presented herewith a first instalment. In order 

 that they may lose none of their value as an inter- 

 pretation of D'Orbigny's views, it is our intention 

 to enumerate them in the same order, and with the 

 same names as they appear in the Memoir already 

 alluded to. 



Fig. 75. Nodosaria Fig. 76. Dentalina Fig. 77- Dentalina 

 limbata. aculeata. communis. 



1. The first genus illustrated is Nodosaria, and 

 its species Nodosaria limbata (fig. 75). The locality 

 assigned is Meudon, where it is said to be very rare : 

 in Morris's Catalogue it is enumerated as British, 

 from Charing. 



2. Dentalina follows, as a sub-genus of Nodosaria, 

 with its first species, Dentalina aculeata (fig. 76), 

 and it is said to be common at Sens, and more rare 

 at Meudon, and in England. It is included in 

 Morris's list as contained in English chalk, and the 

 upper lias at Ilminster. 



3. The next is Dentalina communis (fig. 77), found 

 sparingly at Meudon, in the tertiary of Italy, the 



crag of Bridlington, coralline crag at Sutton, and 

 living in the Adriatic Sea. 



Fig. 78. Dentalina gracilis. 



Fig. 79. Dentalina nodosa. 



•1. Dentalina gracilis (fig. 78), from Sens, is also 

 represented in British chalk, in the Gault at Folke- 

 stone, and in the chalk of Bohemia. It is referred 

 to and figured by Williamson in the Transactions of 

 the Manchester Geological Society. 



5. Dentalina nodosa (fig. 79) is said to be com- 

 mon at Sens, but uncommon at Meudon and St. 

 Germain. It is doubtfully recorded by Morris, in 

 Britain, from Charing. 



Fig. 80. Dentalina Lorneiana. Fig. 81. Dentalina sulcata. 



G. Dentalina Lorneiana (fig. 80), from Sens. 

 Occurs also in the chalk of Kent, and in Bohemia, 

 the latter locality being on the authority of Reuss. 



Fig. 82. Dentalina multicostata. 



7. Dentalina sulcata (fig. 81) is stated to be 

 very common at Sens, Meudon, St. Germain, in the 

 greensand of the environs of Mans, and in the 

 chalk of England. It is not the Nodosaria sulcata 

 of Nilsson, which has occurred at Charing, and in 

 the Gault at Folkestone. 



8. Dentalina multicostata (fig. 82) is the last 

 in the genus, and the first not named in the list of 



