1885.] NEW YORK ACADEMY OF SCIENCES. 33 



their structure. It is Cuviei-'s foui-tli grand divisiou or type tliat 

 sutfers the most change, the Riullata — those h)\v creatui-es that are 

 represented by the sea-stars, sea-urchins, sea-jellies, sea-flowers, 

 corals, and some other low forms. His interpretation of the 

 radiated structure, though clear enough as to many groups, was 

 obscure in some, such as the worms and some of the lowest 

 forms. 



Lamarck, Cuvier's contemporary, did not fully acquiesce in 

 the hitter's favorite scheme of nature, and published his own 

 plan of the animal kingdom, making the two divisions of 

 vertebrates and invertebrates especially significant. This, of 

 course, is a natural and inevitably permanent initial classifica- 

 tion, whatever else may be grouped around it. 



Ehrenberg classed animals as those with continuous solid 

 nervous centres, and those having only scattered nervous 

 swellings. This was but another feature of the former, or an- 

 other way of expressing the same thing; for those forms that 

 have continuous solid nervous centres are the higher animals 

 that need and have a solid, bony skeleton to protect such import- 

 ant nervous centres, whose very integrity depends on their pi-e- 

 servation intact, while the scattered nervous swellings are charac- 

 teriatic organs of the invertebrates, whose integrity does not rest 

 with the ])reservation of the creatures as a whole. 



The second period or era of the history of zoology, we have 

 seen, is coincident with the revival of learning in the sixteenth 

 century. 



One of the earliest woi-ks of this period, or near it, is the Ortus 

 Sanitatus, printed in 1485 — now an exceedingly rare book. 



From the grotesque rudeness of the figures, it would seem to 

 be one of the first to make use of woodcut engravings. Belonius. 

 ■early in 1500, is an important author. Several editions of his 

 works are extant. Belonius failed to recognize the jihilosophy 

 of the system of Aristotle, but he produce*! a satisfactory 

 arrangement of his subjects, considei'ing the time in which he 

 lived, that gained for him a distinguished reputation. In 1554 

 Eondelitius, the Italian naturalist, distinguished himself by his 

 writings on natural histoiy. And while his work abounds with 

 excellent and accurate, though coarse engravings, and is hand- 

 somely embellished, yet it ])erpetuated the monstrous figures of 

 nondescripts, products of the wildest imaginings. Shells are 

 treated with the fishes, and the subjects of insects and zoophytes 

 follow with little system, but that implied in the succession. 

 Aldrovandus and Gesner now appear in ponderous folios, carrying 

 learning, clothed in all the dignity of large illuminated letter- 

 press, and florid title pages. They are little else but copies of 

 preceding books, or compilations of them. The same figures 



