130 THE MIDDLE PAST. 



life become more abundant, reptiles aquatic, terrestrial, and 

 aerial herbivorous, carnivorous, and omnivorous are now 

 the dominant forms, and discharge in their every function 

 the part now assigned to the several grades of the higher 

 mammalia. 



The marine plants of the oolite, like the marine flora of all 

 other geological formations, are indistinct and fragmentary. 

 Their bifurcating impressions are not unfrequent in some 

 of the oolitic sandstones, but such names as halymenites 

 indicate a resemblance rather than a determinable affinity 

 to any living form. Aquatic plants, resembling the pond- 

 weeds (chara, naiadites, and the like), occur in considerable 

 abundance, but little has been done to fix their true rela- 

 tions to existing orders, and in the mean time we can do 

 little more than note the fact of their presence, and indi- 

 cate the conditions that must have favoured their develop- 

 ment. Among the lower or cryptogamic orders of land- 

 plants, equisetums (equisetites), and club-mosses (lycopod- 

 ites), though not so frequent as in earlier formations, are by 

 no means uncommon ; while tree-ferns (pecopteris, splien- 

 opteris, tceniopteris, otopteris, &c.) appear in vast profusion, 

 and many of them peculiar to and restricted to the period. 

 Stems and leaves of unknown endogens (endogenites), palms 

 (palmacites), and lily-like plants occur throughout the for- 

 mation, while cycadaceous stems, leaves, and fruits (cycade- 

 oidea, palceozamia, zamites, pterophyllum, zamiostrobus, 

 &c.) constitute one of the most noticeable botanical peculi- 

 arities of the period. Coniferous trees are also in the 

 ascendant, and so similar in many respects to the cypresses, 

 araucarias, thujas, yews, and pines of southern latitudes, that 

 their affinities are at once expressed by such terms as cupres- 

 sites, araucarites, thuyites, taxites, and pinites. Altogether, 

 the vegetation of the oolite presents a high specific as well 



