CLASS OF CEUSTACEA. 451 



phoses of the young, elucidates the history of the organic 

 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 under- 

 stood. 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 descriptive and philosophical anatomy, to 

 which must be superadded the careful observation of external 

 characters. Hefe are Mr. Goodsir's remarks : 



* There is no set of animals which has caused greater annoy- 

 ance to systematists than the cirrhipeda. 



' They were first arranged by Linnseus along with the tes- 

 taceous mollusca. Cuvier at first followed this arrangement, 

 but latterly placed . them iu 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 crusta- 

 ceans, 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, and changed into young barnacles.' 

 The above-mentioned statements set at rest, in a great mea- 

 sure, the previous discussions as to the position of the cirrhi- 

 peds in the animal kingdom. 



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

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

 movements of some very large balani (Balanus Tintinna- 

 bulum), we observed a few of them ejecting with considerable 

 force a great quantity of small granules every time the cirrhi 

 were retracted. No great attention was paid to this at the 

 time. Next day, however, we were astonished to find the 



* Dr. Held was my student and assistant for severul years ; he was a dili- 

 gent anatomist. R. K. 



