FOSSIL FAUNA. 143 



PLATE LXII. 



Fossil Foraminifera. 



With the exception of figs. 23, 24, 29, 31 and 32, all the specimens delineated in this Plate 



belong to the Foraminifera. The figures represent magnified views; the natural size is indicated 



in some instances by a minute outline. Under the article " Foraminifera," in the " Supplementarii 



Notes,''' a general account is given of the structure and economy of the living animalcules. 



A list of names is subjoined. 



Figs. 1, & 2. Rotalia trochiliformis, of Lamarck. Tertiary. 



Fig. 3. Rotalia Beccarii, of Linnjeus. Tertiary. 



Fig. 4. Cristellaria rotulata, Lamarck. Chalt. 



Figs. 5, 6, 7. Lituola nautiloidea, Lamarck. Chalk. 



Fig. 8. Spirolina depressa, Lamarck. This and the specimens to fig. 21 inclusive, are tertiary 

 fossils. 



Fig. 9. Spirolina cylind/racea, Lamarck. 



Fig. 10. Orthocerina clavulus. 



Fig. 11. Biloculina ringens, Lamarck. 



Figs. 12, & 13. Quinqueloculina cor anguinum, Lamarck, 



Figs. 14, 15, & 16. Quinqueloculina. 



Figs. 17, 18, 19. Trilooulina trigonula, Lamarck. 



Fig. 20. Quinqueloculina opposita, Lamarck. 



Fig. 21. Peneroloplisopercularis. 



Fig. 22. Adelosina, of D'Orbigny; a recent species. 



Figs. 23, & 24. Gyrogonites. The fossils here figured on a magnified scale as microscopic shells 

 of the same family as those above described, received the name of Gyrogonites, or 

 twisted stones. They prove to be the seed-vessels of a species of the common fresh- 

 water plant, the Ghara. The fruit of this genus consists of minute nuclei, with an 

 external calcareous covering, composed of five spirally twisted plates, which unite at 

 the summit. These fossils occur by myriads in many of the fresh-water secondary 

 and tertiary limestones, as well as in the calcareous deposits now in progress of 

 formation in our lakes. In the lacustrine limestones of the Isle of Wight (at 

 Binstead, White Cliflf', &c.), beautiful specimens may be obtained.' Professor 

 E. Forbes has discovered Gyrogonites in the Wealden strata of the Isle of Purbeck, 

 associated with shells of the genera Planorbis, Physa, Paluolina, &c. 



' See Geological Excursions round the Isle of Wight. 2d Edit. 1850, p. 108. 



