494 ZOOLOGY. 



of many living species typify, or are types of, adult forms or 

 species now extinct ; that is, of the adult forms of the fossil 

 world. Thus it is that the history of the organo-genesis, of the 

 metamorphoses of the young, elucidates the history of the or- 

 ganic world, past and present, connecting them together into one 

 great whole, the accomplishment of one vast design. The laws 

 of deformation, even in man, are as yet but little understood. 

 One thing is certain ; namely, that for the future zoology cannot 

 be based on any exclusive method or mode of research, but must 

 seek for its illustrations and views in the entire range of descrip- 

 tive and philosophical anatomy, to which must be superadded 

 the careful observation of external characters. Here are Mr. 

 Goodsir's remarks : 



' There is no set of animals which has caused greater annoyance 

 to systematists than the cirrhipeda. 



'They were first arranged by Linnaeus along with the testa- 

 ceous mollusca. Cuvier at first followed this arrangement, but 

 latterly placed them in a distinct class by themselves, between 

 the mollusca and articulata. Lamarck, Latreille, M'Leay, and 

 other authors, followed this latter arrangement ; the two last 

 authors acknowledging, at the same time, their closer connexion 

 with the articulata. 



'The decision of this important question, however, was left to 

 our countryman, Mr. J. V. Thompson. This gentleman having 

 obtained some minute mussel- like animals, at first considered 

 them to be nondescripts belonging to the crustaceans, but on a 

 further examination, and by keeping a few of them alive in glass 

 vessels of sea-water, he was soon enabled to make out their 

 nature and relations satisfactorily. To use Mr. Thompson's own 

 words ' They were taken on the 1st of May, and on the night 

 of the eighth the author had the satisfaction to find that two of 

 them had thrown off their exuvia, and wonderful to say, were 

 firmly adhering to the bottom of the vessel, a^d changed into 

 young barnacles.' The above-mentioned statements set at rest, 

 in a great measure, the previous discussions as to the position of 

 the cirrhipeds in the animal kingdom. 



' In the beginning of March of the present year (1843), while 

 Professor Reid* of St. Andrews and myself were watching the 

 movements of some very large balani (Balanus Tintinnabidum), 

 we observed a few of them ejecting with considerable force a 

 great quantity of small granules every time the cirrhi were re- 

 tracted. No great attention was paid to this at the time. Next 

 day, however, we were astonished to find the basin in which the 

 balani were confined swarming with an innumerable number of 



* Dr. Keid was my student and assistant for several years ; he was a dili- 

 gent anatomist. E. K. 



