TKANSACTIONS OF THE SECTIONS. 131 



Oil tlie priuciple of molecular coalescence from the uuiou of viscid or colloid material 

 witli earthy or organic crystalloid matter, in the maimer of the formation of the 

 dental tissues and shell-structures described by Mr. George Rainey. 



_ To these three different modes of constitutional calculus formation the author 

 gives the respective names of Crystalline, Ciystallo-coUoid, and Molecular coales- 

 cence. In concluding, the author remarked that the calculi he had been describing 

 must not be confounded with those which, for the sake of distinction, might bo 

 termed " accidentally acquired," such as vesical, which frequently have for their 

 nucleus foreign substances, such as a pea, a barleycorn, a piece of bone, hair, wire, 

 a fragment of sealing-wax, or a portion of catheter, the irritation of which excites 

 the presence of tenacious mucus, blood, or even pus, with which the foreign body 

 itself becomes coated, and in and around which crystalloid molecules and actual 

 crystals are deposited and form the calculus. 



Lastly. Calculi are not always of uniform composition throughout. Their com- 

 position varies at different times with the different states of health of the patient. 

 The centre of the concretion may be composed of uric acid, then may come a layer 

 of oxalate of lime, and over that another layer of uric acid or of phosphate, so that 

 in a section of a calculus the clinical phases through which a patient has past may 

 be read as truthfully as the geologist can read the earth's history in the strata 

 forming its crust. 



0)1 the Structure of the Egr/, and the early Development of the Oephahpod 

 Loligo. By E. Eat Lankesteh, M.A., Exder College, Oxford. 



The author discussed some points as to the nature and mode of formation of 

 eggs, in connexion %vith his observations on the &g^ of the cuttlehsh, Loliyo. 

 Every egg is originally a small corpuscle of protoplasm, like those which btuldup 

 the tissues of animals ; but it acquires additional substance, and in some animals 

 (for instance, birds) becomes very large before it is laid. The additional substance 

 differs in its character in different animals. In Apus fom- original egg-corpuscles 

 fuse and form one egg, from which one embryo develops. In most cases the eoo* 

 grows in the ovary by receiving nutrition from the blood ; but in many cases (In 

 birds, fishes, and in cuttlefish) the egg is contained in a capsule, which is lined 

 with living corpuscles, and these are continually multiplying by division, and 

 pass from the capside into the e^^^ to increase its bulk. "Tliis Mi\ Laukester had 

 demonstrated by sections in the case oi Loliyo. So far he agreed with Prof. His; 

 but he did not find that these corpuscles remained alive and helped to form the 

 embryo cuttle fish. The egg of Loligo when laid was a perfectly homogeneous 

 mixture of albuminous matters of («) the original egg-corpuscle, {h) the corpuscles 

 from the capsule, and (c) the male spermatozoa. From this mixture there segre- 

 gated at first to one pole plastic matter, which broke up into corpuscles (" klasto- 

 plasts ") forming a cap (yelk-cleavage). Outside this cap of cleavage-corpuscles 

 other large corpuscles (" autoplasts ") then made their appearance by a new and 

 independent process of segregation (free cell-formation) ; and these became branched, 

 forming a deep or middle layer in the embryo, whilst the cleavage-corpuscles spread 

 over them at a higher level. 



'O* 



Microzymes as partial Bionta. By Dr. John lloss. 



Note on Huizinga's Experiments on Ahiogenesis. By Dr. Burdon Sandebsox. 



Under the title of a " Contribution to the question of Abiogenesis," Prof. 

 Huizinga has very recently published (Pfliiger's Archiv, vol. vii. p. 649) a series of 

 experiments which deserve notice, as conslituting a new and carefully worked out 

 attempt to support the doctrine of spontaneous generation. 



Prof. Huizinga begins his paper with the words " Multa reuascentur quae jam 

 cecidere," using them as an expression of the recm-ring nature of this question. 

 He then proceeds to say that he was induced to undertake his inquiry by the 

 publication of the well-known work by Dr.- Bastian (whom ho compliments as 



