22G FOURTH REPORT — 1834. 



number of his Zool. Researches, containing some observations 

 on the Cirnpeda which appear to be quite decisive of their close 

 affinity to i\ie Annulosa in general, and the Branchinpod Crus- 

 tacea in particular. This gentleman asserts that he has ob- 

 served that these animals undergo a metamorphosis. He states 

 having discovered swimming freely in the sea a small crusta- 

 ceous animal furnished v^^ith a shell composed of two valves like 

 those of Daplinia ; that being desirous of watching it further, 

 he kept it in water, and was much surprised, after a few days, 

 at seeing it throw off its bivalve shell, attach itself to the bottom 

 of the vessel, and become transformed into the Balanus piisillus 

 of Pennant*. For some time afterwards these alleged facts 

 were thought to require confirmation from other observers ; 

 more esiiecially as in a commvmication made to the Zoological 

 Society last yearf, Mr. Gray advanced some statements re- 

 specting the condition of the j^oung oi Balanus Cranchii (Leach) 

 observed in ovo, as well as of the young of the genera Pentelas- 

 niis and Otion, which appeared to militate against the accuracy 

 of Mr. Thompson's views. They have, however, been fully 

 established by Dr. Burmeister, who has recently published a 

 treatise on these animals annoiincing this circumstance j and 

 judging from his own observations, combined with those which 

 had been previously made by others, Dr. Burmeister infers that 

 the Cirripeda ought to be arranged with the Crustacea, forming 

 a particular tribe in that class J. 



It may be stated that M. Martin-St.-Ange is said to be en- 

 gaged in a work on the organization and affinities of the Cirri- 

 peda. The results of his researches have been already given to the 

 public in a memoir read to the Royal Academy of Sciences at 

 Paris towards the end of last year§. They likewise favour the 

 opinion that these animals, at least the pedunculated genera, are 

 truly articulated, and allied to the lower forms of Crustacea. 

 M. Martin-St.-Ange thinks that they also show some points of 

 affinity to the Annelida. 



* It is a curious fact that, according to Mr. Thompson, the young animal 

 should not only possess the power of locomotion, which is denied to the adult, 

 hwi distinct organs of sight, which, after the transformation into £a/a»i, gra- 

 dually become obliterated. This is analogous to Edwards's observation (already 

 alluded to) in the case of the development of the Cyinothoce. It is, however, 

 yet more striking. 



t See Proceed, of Zool. Soc. (1833), p. 115. 



X The above statements are on the authority of De F^russac's Introduction 

 to his recently published Monograph on the Cephalopoda. I have not seen 

 Burmeister's work myself, which is said to be entitled Beitrage »ur Naturge- 

 schichte der Rankenfiisser. 4to, Berlin, 1834. 



§ See L'Institut, No. 27. p. 226, and No. 62. p. 231. 



