262 J^ew Publications. [April, 



cups arranged along a tubular axis. The second, actinoidea com- 

 prises the common coral forming animals. 



Mr. Dana gives a full and admirable description of the two 

 orders, with cuts illustrating many of the generic and specific 

 distinctions. 



We copy a few additional facts, those which will give our 

 readers a more full and perfect idea of the nature of the animals 

 belonging to the first order. 



They have no glandular system; no special absorbent or cir- 

 culating system; no ovarian glands, and no distinct nervous sys- 

 tem. Every part seems equally a centre of organic forces, and 

 consequently sections made almost indefinitely still live and com- 

 plete the entire polyp again. 



These minute beings constitute the mosses of the coral land- 

 scape, the carpeting of marine beds. The corals or actinoidea 

 are likened to the larger plants, the asters, carnation and anemo- 

 nes which deck the marine garden; the astreas and gorgonias 

 make the shrubbery. 



Passing over nearly one huncked pages of Mr. Dana's work, 

 some parts of which we would have been pleased to have no- 

 ticed, had we time to furnish the necessary illustrations, w^e pro- 

 ceed to notice very briefly his remarks on the distribution of zoo- 

 phytes. 



The agents which influence the distribution of all animals 

 operates upon these in a special manner. Heat, light, pressure, 

 and means of subsistence, are the agents which exert the strong- 

 est influence in their distribution. Heat is the most important in 

 giving them latitudinal range, while light and pressure determines 

 the limits in depth. While these causes fix bounds to species 

 and families they do not necessarily confine tribes of species to so 

 small limits. 



The hydroidea are found in all seas and at great depths, as well 

 as at the surface. 



It is in the torrid zone that the actinoidea display their greatest 

 numbers and beauties. The coral reefs which sometimes extend 

 a thousand miles, are like a thousand miles of a thick tangled 



