41 



Steenstrup. These characteristics of his Essay have procured 

 for it a wide and favourable reception ; and the terms in 

 which he has summed up the facts are now commonly 

 received both here * and on the Continent in the sense in 

 which he has proposed them, viz. as explanatory of the 

 phenomena so generalized. It is against this arrest of 

 inquiry and judgment that I now chiefly argue, from a con- 

 viction that a better explanation of the phenomena may be 

 given, or, I should rather say, a real explanation, so far as 

 it goes, as compared with the seeming explanation accord- 

 ing to the terms of the e alternate-generation 5 theory. 



I am not, however, the only English physiologist who 

 has submitted the true value of this theory to examination. 

 The able author of the article on Sir John Graham Dalyell's 

 beautiful work " On the Rare and Remarkable Animals of 

 Scotland" in the e Annals and Magazine of Natural Hi- 

 story 5 (1848, p. 312), has pointed out some of the facts 

 which he deems irreconcileable with Steenstrup's theory : 

 and Dr. Carpenter, in a valuable paper on the same subject 

 in the Medico-chirurgical Review, 1848, has rejected the 

 theory in stronger terms of condemnation than I think 

 are applicable to it. The latter reviewer says that Steen- 

 strup " has built up a very plausible hypothesis upon the 

 foundation of the phaenomena of metamorphosis pre- 

 sented by the zoophytes and acalephae," and charac- 

 terizes it as " a very premature, erroneous and limited 

 expression of the real facts" (p. 192) ; affirming that "Pro- 

 fessor Steenstrup has laboured under a total misconception 

 of the most important part of the process" (ib.), his propo- 

 sitions being " totally inapplicable to the vegetable king- 

 dom." And Dr. Carpenter offers what he believes to be " a 



* " I see no reason, therefore, to dissent from the theory of Steen- 

 strup : it is the simplest and most intelligible, as well as the most 

 original expression hitherto offered of the astonishing facts which he 

 was the first to generalise." Prof. Ed. Forbes, ' Monograph on the 

 Naked-eyed Medusae/ p. 88. 



