THE PROGRESS OF LIFE 79 



leaved Gingko-pine (Salisburia) of China, but it had a 

 large pith ; while Cordaites appears to have been a 

 Cycad, with relations to the broad-leaved yews on one 

 hand, and to Sigillaria on the other. Cordaites and 

 the large Lycopods attained their maximum in the 

 Carboniferous period. 



This flora spread over North America, Europe, 

 South Africa, India, and Australia ; but no trace of it 

 has as yet been found in New Zealand, nor in South 

 America. 



At the close of the Carboniferous period the large 

 Lycopodiaceae and Cordaites died out ; and only a few 

 species of Calamites lingered on into the Permian, the 

 flora of which was composed of ferns, cycads, and 

 conifer ae, especially the last. 



In the Devonian period Neuropterous insects (May- 

 flies) came on the scene; and in the Carboniferous 

 forests were many others belonging to the Orthoptera 

 (Cockroaches and Locusts) and Hemiptera. But there 

 were no beetles, moths, flies, ants, or bees ; while, in 

 addition to millipedes and scorpions, we now find 

 spiders and land-shells. 



The first land-vertebrates were Amphibians, or 

 Batrachians ; which change their mode of respiration 

 from aquatic to aerial during their life, and are easily 

 distinguished from fishes by their nostrils. They were 

 represented in the lower Carboniferous period by the 

 LalyrintJiodontia, so named from the labyrinth-like 

 appearance of a transverse section of a tooth, owing 

 to its complicated folded structure, which is something 

 like that of the early Crossopterygii. The Labyrinth- 

 odonts died out at the end of the Triassic period, and 

 were most abundant in the Permian, when they 



