TRANS ACTIONS OF THE SECTIONS. 139 



transfusion of any simple saline fluid into the veins, as has been tried in the case 

 of animals poisoned with chloroform, and as in the analogous collapse of cholera. 



On a Hydro-spirometer. By Dr. Lewis. 



On the Development o/Buccinum. By John Lubbock, F.R.S., F.L.S. 



In the year 1851 MM. Koren and Danielssen published a memoir* on the 

 Development of the Eggs of Buccinum undatum and Purpura lapilhis, in which 

 they gave an interesting account of the development of the young mollusks, and 

 especially excited the surprise of naturalists by certain statements regarding the 

 amalgamation of several eggs to form one embryo. 



The two above-mentioned species produce peculiar capsules, each containing 

 several hundred eggs. The capsules of Purpura are bottle-shaped, those of Buc- 

 cinum are like a round cushion, and are attached to one another in clusters, and 

 fastened to rocks, shells, or sea-weeds. Often, however, they are detached and 

 thrown up on the shore, so that they are familiar to all those who ever walk along 

 the beach near high-water mark. The egg-capsules of Purpura are attached singly 

 to the rocks. It was already known that, although each capsule contained a great 

 number of eggs, only a small number of embryos, from fifteen to thirty, came to 

 maturity. 



MM. Koren and Danielssen gave a very extraordinary account of the phenomenon. 

 According to them the eggs grouped themselves in masses, round which a common 

 skin was formed, and thus numerous ova combined to form one embryo. This 

 account of a process, so different from that with which we are familiar in other 

 animals, was not likely to pass long without either confirmation or opposition ; and 

 accordingly Dr. Carpenter f, having studied the development of the eggs of Purpura 

 lapillus, disputed some of the statements made by MM. Koren and Danielssen, gave 

 a very different explanation of the whole phenomenon, and added the high authority 

 of Messrs. Busk and Huxley in confirmation of his view. 



Dr. Carpenter had no opportunity of making any observations on the embryology 

 of Buccinum, but he convinced himself that the cgg-capsides of Purpura lapilhis 

 contain two sorts of bodies, namely true eggs and " yolk-spheres," which, however, 

 are at first undistinguishable from one another. After a while, however, "all the 

 egg-like bodies in the capsule begin to show signs of cleavage. In the greater part 

 of them, the two segments produced by the first cleavage are equal, or nearly so ; 

 and each of these again subdivides into other two, which are alike equal ;" after 

 which the division becomes irregular. These are the so-called "yolk-spheres." 

 Some few of the egg-like bodies, on the contrary, divide into two unequal segments. 

 These are the true eggs, and each embryo takes its origin from one of these. The 

 embryo then developes rapidly in itself a central hollow or stomach, a wide oeso- 

 phagus, and two lobes covered with cilia. It then commences to swallow the yolk 

 matter around it, and this is the reason that the number of embryos is so much 

 smaller than that of the egg and yolk-spheres. 



MM. Koren and Danielssen by no means gave up their theory, but after repeat- 

 ing their observations, they reiterated their statements J, giving, however, it must 

 be confessed, figures much more nearly resembling those of Dr. Carpenter than the 

 ones contained in their first memoir. 



Finally, Dr. Carpenter, in the 'Annals and Magazine of Nat. Hist.' for 1857, has 

 published some further remarks on the subject, and adds, in addition, the testimony 

 of Dr. Dyster to the truth of his assertions. This is the present state of the ques- 

 tion; and considering how common are the egg-capsules of Buccinum, it is remark- 

 able that no one has tested MM. Koren and Danielssen's statements in reference to 

 that genus. 



The whole subject is one of great interest ; and though I could not doubt the 

 truth of statements made from independent observations by four such excellent 

 authorities as Messrs. Carpenter, Busk, Huxley, and Dyster, yet MM. Koren and 



* Bitrag til Pectinibrancliiernes Udviklingshistoire. I have not seen the original work 

 but there is a translation of it in the Ann. des Sc. Nat. for 1852. 

 t Quarterly Journal of Microscopical Science, vol. iii. p. 17. 

 J Fauna Littoralis Norvegise, vol. ii. 



