4 THE POLYZOA RECOGNISED AS 



the same field, and his researches, which were thus entirely independent, led him to the 

 conclusion, " that these apparent plants were ramified animals in their proper skins or 

 cases." In 1755, he published his famous 'Essay on the Natural History of Corallines,'* 

 a work which in profuseness and fidelity of observation, in lucidity of description, and in 

 pictorial illustration, seemed to leave little else to be accomplished. 



Linnaeus, who, as we have just seen, met the animal theory only half way, was never 

 entirely convinced ; he continued, too, for some time, to have his followers, but Ellis had 

 sapped the very foundations of the vegetable theory, and in a few years, notwithstanding 

 bitter opposition from some isolated quarters, the question was finally set at rest in the 

 general admission of the animality, not only of the true corals and madrepores, but of all 

 those flexible and horny productions whose plant-like form was at such variance with every 

 previously conceived notion of animal existence. 



It was not yet suspected that among these curious " zoophytes," so like one another in 

 external form, there were still two totally distinct types of animal organization ; and the 

 attention of naturalists M^as now chiefly directed to the comparison of external characters for 

 the determination of species, and as the grounds of classification. Numerous systems were 

 accordingly from time to time proposed, which, however, were all more or less artificial, and 

 involved the fundamental error of assuming the external calcareous or horny covering as a 

 character of primary importance, and, as a necessary consequence, the association of forms of 

 a widely difi"erent plan of structure. 



In the mean time the number of known species had greatly increased, and collections, 

 both on our own and foreign shores, had enriched this department of natural history to an 

 extent of which few others could boast. Important improvements too had taken place in our 

 means of observation, and the value of anatomy in the determination of the true rank of 

 organic beings had been very generally recognised. Zoologists were thus prepared to appre- 

 ciate the importance of the new light which was about to be thrown upon the structure of 

 these plant-like productions. 



In March, 1827, Professor Grant read before the Wernerian Society a Memoir on the 

 structure of Flustrse.f In this Memoir the author has described the locomotive embryos of 

 Flustrse ; he also gives an account of the animals of Flustra carbasea and F. foUacea, and shows 

 them to be quite difi'erent from the hydroid polype of the Sertularice ; but he seems as yet to 

 have had but an imperfect knowledge of them, and I cannot find anything in the Memoir to 

 justify the belief that this excellent zoologist was acquainted with the complete intestinal 

 canal of the animal. 



In September of the following year MM. Auduin and Milne-Edwards presented to the 

 Royal Academy of Sciences, in Paris, a summary of their researches on the invertebrate 

 animals of the Chausey Isles, a group of small rocky islands off the coast of France. Among 

 these researches the investigations of M. Edwards into the Flustrae hold a prominent place. 

 No one could have come better prepared for the task than the celebrated French zoologist. 

 Already long devoted to the study of the invertebrate animals, and just fresh from a series of 



* ' Essay towards a Natural History of the Corallines and other Marine productions of the like 

 kind, commonly found on the Coasts of Great Britain and Ireland,' London, 1755. 



t Observations on the Structure and Nature of Flustrse, ' Edinb. New Philosophical Journal,' 

 vol. iii, 1827. 



