TBANSACTIONS OF SECTION D. 755 



First, the activities of animals have to be carefully observed as objective phenomena. 

 Secondly, our own mental processes have to be carefully observed, and cautious 

 inductions have to be drawn therefrom. Finally, the objective phenomena 

 reached by the first process of observation have to be interpreted in terms of the 

 conclusions reached through the application of the second process. Naturalists 

 are too apt to forget that the second process is as essential as the first, and that to 

 do good work in comparative psychology it is necessary to be a psychologist. 

 Neither process of observation can be omitted if results of scientific value are to be 

 reached, for both are of co-ordinate importance. 



Psychological analysis is beginning to make clear the nature of the feeling and 

 perception of relations. It also discloses that there is a well-marked contrast 

 between (1) the mere feeling or practical awareness of relations, and (2) the definite 

 perception or cognition of relationships. The former is the foundation of practical 

 skill; the latter is the foundation of explanation and knowledge. The former is 

 manifested in the simple psychical life of external perception ; the latter involves 

 introspection and reflection. 



In the higher animals there is abundant evidence of ability to feel and respond 

 to relations, and of wonderful practical skill based on direct experience. There is 

 little or no evidence of the perception or cognition of the relations, of introspection, 

 or of reflection. It is well to restrict the words ' reason ' and ' rational ' to the latter 

 process. Animals are certainly intelligent ; they may be rational. 



4. On the Uelatlonsliips and Hole of the Archoplasniic Body daring 

 Mitosis in the Larval Salamander. Bij J. E. S. Mooke, A.B.C.S. 

 Bond. 



The existence of the ' Nebenkern ' as a frequent cellular constituent has been 

 pointed out by a variety of authors whose descriptions relate to vertebrates and 

 invertebrates alike, but hitherto certain elements of confusion, arising from the 

 simultaneous description of other bodies, obviously heterogeneous and foreign, have 

 relegated this structure to a position of only secondary importance in cellular 

 anatomy. 



Our most accurate knowledge of the ' Nebenkern ' is derived from Platner's 

 admirable description of its origin and metamorphosis in the spermatocytes of 

 Heli.r, where it plays so marked a part in the indirect division of the cell. 



Hermann's more recent description of an archoplasmic body in the sperma- 

 tocytes of the salamander, and his institution of a probable homology between this, 

 the 'Nebenkern,' and the 'sphere attractive' of Van Beneden, renders the possible 

 extension of these observations to other kinds of cells a matter of primary interest 

 to those desirous of embracing under some more general formula the varied 

 phenomena of mitosis. 



The duplication of the spheres in Ascaris, as compared with the single archo- 

 plasmic body in the spermatocytes of Salamandra ; the invariable appearance and 

 relationship' of a central body or bodies, of the ' medullary corpuscle ' and outer 

 ' archoplasm ' in the former ; and the frequent absence of ' medulhuy zones,' 

 central body, or both, from the archoplasm of the latter, are considerations 

 antagonistic to the desii-ed demonstration of the above homology. 



Much of this confusion is dispersed by discoveries in the embryonic genital 

 ridge of the salamander. In this tissue the archoplasmic body is much more 

 definite than in the spermatocytes, and may become duplicated, as in the ' spheres 

 attractives ' of Ascaris. 



It presents a serial metamorphosis identical with that of the spermatocytes of 

 Helix. During certain phases of this, the relationships of the central body, zone, 

 and archoplasm are identical with those existing in the spheres of Ascaris. 



The interest and significance of the above observations are greatly increased by 

 the discovery of an archoplasm (' Nebenkern,' ' sphere attractive ') in certain 

 phases of the life history of tlie leukocytes in the same amphibian larvaj. The 

 existence of the archoplasm (' Nebenkern ') in the cells constituting the uuditTereu- 



3 c 2 



