CURRENT LITERATURE. 55 



observers trace them to the mesoderm. We do not think that our author's observa- 

 tions on this point will meet with general acceptation, especially as his figures are 

 by no means conclusive. The origin of one of these organs, the heart, has been 

 traced so conclusively to the mesoderm in so many invertebrates, that we do not 

 think a couple of isolated cases like these, even supposing them to be correct, can 

 invalidate it. 



Our author traces the origin of all the remaining organs in the same detailed 

 manner, but unfortunately, as it appears to us, he loses sight of the broader features 

 of the homology and morphology of the organs in the study of the origin of their com- 

 ponent cells. We cannot help thinking that ontogenists are tending to lose their 

 powers of discrimination, so far as features of phylogenetic significance are con- 

 cerned, in the minutiae of the ontogeny of the individual. The true study of phy- 

 logeny can only be based upon a combination of comparative morphology and 

 embryology, certainly not upon the study of embryology alone. In this respect, we 

 think, Professor Sedgwick was right in his vigorous attack upon von Baer's hypothesis 

 that ontogeny recapitulated phylogeny, though he possibly carried his onslaught 

 upon the law of recapitulation too far, but that such a warning was necessary we 

 see daily in the ever increasing detailed ontogenetic works, and the phylogenetic 

 conclusions based thereon. 



Dr. Meisenheimer concludes with a careful comparison of the Trochophore of 

 Dreisscnsia with those of other Mollusca and Annelida, but even here we cannot 

 help thinking that he has been led astray in concluding that the Trochophore is of 

 such great phylogenetic importance. He himself states that he formerly held the 

 reverse view, and, we think, if he had not restricted himself so much to ontogeny, 

 he would still regard this interesting and undoubtedly important larval form as 

 having less phylogenetic significance than he now assigns to it. 



Unfortunately owing to the iniquitous system at present in vogue, all the cream 

 has been skimmed off this paper by the publication of no less than three preliminaiy 

 communications, two of them being illustrated. Personally we utterly fail to under- 

 stand why anyone should wilfully set to work to spoil his own work in this way, 

 and can only express the pious wish, that the lime will come when that horror the 

 preliminary communication shall trouble us no more. — M. F. Woodward. 



MaeMunn, C. A.— On the Gastric Gland of Mollusca and Decapod Crustacea : 

 its Structure and P\mctions. Phil. Trans. Roy. Soc. , 1900, P. vol. 193, 

 PP- 1—34, pls. 1—4- 



The objects of this investigation, the author states, were "to determine (i) the 

 form in which entero-chloropliyll and the associated pigments occur in the glandular 

 epithelium of the gastric gland ; (2) the nature of the bodies with which the pigment 

 is associated * * ; (3) how this pigment is formed in the gland ; and (4) if not 

 actually formed there, how does it get into the glandular epithelial cells ; " finally 

 the relation (if any) of Chaetopterin to entero-chlorophyll, and the general histology 

 of the gland are discussed. 



From an examination of Ostrca, Patella, Aphjsia, Helix, Limax, and Arion, 

 the author shows that there is a complete absence of glycogen, that the colouring 

 matters are taken up from the intestine and accumulated in the gland, which is 

 capable of storing fat and pigment, and has also an excretory function. 



The author discusses in some detail the results of spectro-photometric observa- 

 tions, and other points mentioned above. 



