550 



NATURE 



[January 20, 1910 



mentally from the various interpretations now being urged 

 by other biologists. 



Putting aside the condition of affairs found in all other 

 Ichthyopsida, the consideration of which would be con- 

 fusing unless there were time to discuss their morphology 

 in some detail, let us look for a moment at the brain of 

 the Dipnoi. In the mud-fish the cortex-like material form- 

 ing the tuberculum olfactorium becomes highly specialised, 

 and forms a relatively enormous organ upon the basal 

 aspect of the cerebral hemisphere, of which it constitutes 

 more than half the bulk. The pallial formation also 

 becomes more distinctly differentiated into a cortex, the 

 lateral part of which can now be justly termed " pyri- 

 form " and the mesial " hippocampal." The fornix-fibres 

 connected with the latter are embedded in a mass of 

 ganglionic matter — the paraterminal body — which exhibits 

 a functional relationship to the hippocampus analogous to 

 that which the striate body presents to the other cortical 

 areas. In other words, it is a nucleus of origin for large 

 numbers of projection fibres which pass down to the hypo- 

 thalamic region, and the cells of origin of these fibres are 

 probably under the influence both of descending hippo- 

 campal (smell) fibres and ascending tracts from the lobus 

 inferior of the hypothalamus (probably taste). 



Leaving the Amphibia out of account, and turning 

 at one step from the Dipnoi directly to the reptiles, it will 

 be found that the highly developed tuberculum olfactorium 

 of the Dipnoi has undergone a great diminution in size 

 and an even more pronounced deterioration in structure, 

 but the corpus striatum and the pallial formation show a 

 great advance both in size and in specialisation of structure. 



There are very definite reasons for rejecting the views of 

 Ramon y Cajal as to the homology of the mesial wall of 

 the reptilian hemisphere, and also von Kupffer's identifi- 

 cation of the hippocampus. Nor can we accept in its 

 entirety the interpretation of the limits of the hippocampal 

 formation and of its constituent parts favoured by Edinger 

 and .Ariens-Kappers. 



The hippocampal formation of the reptile is not broken 

 lip into two parts, fascia dentata and hippocampus sensu 

 stricto, as it is in the mammal, but is a continuous column 

 of cells, as the lecturer pointed out in 1895 — an opinion 

 since confirmed by Giuseppe Levi. 



But there is no fully differentiated fascia dentata in 

 reptiles as Levi believes. The hippocampal formation of 

 51 lizard contains cells analogous to those of the fascia 

 dentata intermingled with others like those of the hippo- 

 campus sensu stricto, and others, again, intermediate in 

 structure between the two. Thus in the reptile the hippo- 

 campal formation is caught, as it were, in the act of 

 differentiating. Ultimately (in mammals) all the hippo- 

 campal cells vanish from its mesial part, leaving only 

 " dentate " cells, which form a receptive organ for in- 

 coming olfactory impulses, and the lateral (dorsal) part of 

 the formation loses all its " dentate " cells and becomes 

 a purely associative and projection-organ. 



In reptiles, the larger size of the corpus striatum and 

 pallial formation is probably related to the fact that many 

 sensory fibres ascending from the optic thalamus make 

 their way into the hemisphere. The researches of Edinger, 

 Wallenberg, Gordon Holmes, .Ariens-Kappers and others, 

 have made it appear most likely that these fibres carry 

 tactile impressions from the tongue and the cutaneous 

 areas around the mouth, and possibly also visual impulses. 



These two categories of fibres are certainly abundant in 

 the peculiarly aberrant and highly specialised brain of the 

 bird, in which the corpus striatum takes on an enormously 

 enhanced importance and significance, and develops along 

 lines which diverge widely from the stream of mammalian 

 evolution. 



In the reptile there is no true neopallium, but great 

 confusion in the relations is produced, because the lateral 

 part of the pallial formation is being suddenly stimulated 

 to expand by the entry of these sensory, and perhaps visual, 

 fibres. The rapidly overgrowing cortex becomes bent into 

 the ventricular cavity to form a pseudo-ganglionic (but 

 really cortical) mass, which Edinger has called Epistriatum. 



In the immediate ancestors of mammals the number and 

 variety of sensory paths which found admission into 

 the cerebrum became enormously increased, and led to a 

 further specialisation of the pallial formation, resulting in 



NO. 2099, VOL. 82] 



the birth of the neopallium — a cortical area where all 

 the sensory impulses brought to the cerebral hemisphere 

 along these new channels might be received, be blended in 

 consciousness with those coming from other sense-organs, 

 and leave impressions which might be stored, as it were, 

 in this neopallium, and so influence other sensations and 

 states of consciousness at some subsequent time. The neo- 

 pallium is thus the organ of associative memory. 



It is, perhaps, not devoid of significance that the first 

 appearance of a definite neopallium coincides with the 

 transformation of the skin over the whole surface of the 

 body into a highly specialised tactile organ. 



The further evolution of the neopallium in the Mammalia, 

 and the formation of sulci and convolutions, was also 

 discussed, special stress being laid upon the value of the 

 unrivalled collection of brains in the college museum for 

 the study of this aspect of the subject. 



CONFERENCES ON SCIENCE AND MATHE- 

 MATICS IN SCHOOLS. 

 T^HE Mathematical Association and the Public Schools 

 Science Masters joined forces at their annual meetings 

 held this month at WestmiiiSter School. We print below 

 a programme of the proceedings, and attempt to indicate 

 the present situation of science and mathematical teaching 

 in relation to the work of these associations, following' lines 

 of thought prompted by the expression of opinion at the 

 meetings. 



We must first discriminate between the Mathematical 

 Society and the Mathematical Association. The former 

 body is devoted to research, the latter to the improvement 

 of elementary mathematical teaching. The organ of the 

 association is the Mathematical Gazette ; one hears com- 

 plaints that disproportionate space is given in its columns 

 to problems of purely mathematical interest or to minutia:, 

 while the clamant need for reconsidering the bases of one 

 of the fundamental branches of ed jcation remains unsatisfied. 



In the course of a vigoiou^: presidential address. Prof. 

 Turner spoke of the reign of efificiency established in the 

 department of Egyptian service under Captain Lyons. For 

 responsible work of varied nature Captain Lyons selected 

 able mathematicians from Oxford and Cambridge. These 

 men proved successful, and Prof. Turner directed attention 

 to this fact in support of his opinion that it is a mistake to 

 strive after a " general education " for all boys. .\ 

 gardener might as well treat his flowers as cabbages. In 

 the paper which foUow^ed, Mr. Godfrey emphasised the 

 importance of paying regard to the different requirements 

 of students. The precise value of algebra in education 

 deserved greater consideration. The remaining papers 

 hardly provided such nutrient fare as one would wish for en 

 an occasion when masters and mistresses from schools all 

 over the country are summoned for annual conference. In 

 the afternoon, however, a crowded meeting discussed the 

 urgent problem of how to correlate mathematical and 

 science teaching, an important report serving as the basis 

 of debate. The committee responsible for the report con- 

 sisted of six representatives of mathematical teaching, six 

 of science, and two head-masters of preparatory schools. 

 They had been asked to consider the possibility of corre- 

 lating the teaching of mathematics and science, and their 

 reply took the effective form of a series of recommendations 

 for putting such correlation into practice. As might be 

 expected from the composition of the committee, all the 

 recommendations were evidently the outcome of practical 

 experience in the class-room. The prime necessity was 

 cooperation betw-een the teachers of the respective branches, 

 and jt'W^as recognised that the chief obstacle was the lack 

 of laboratory training, which w'as, unfortunately, !o 

 coramon amongst mathematicians. To aid in removing 

 this obstacle, an appendix was devoted to the vacation 

 course in practical work organised for schoolmasters at 

 the Cavendish Laboratory : the course was given last 

 .August, and is to be repeated next summer. 



Many of the recommendations are commendable, e.g. that 

 the practical measurements should have a real connection, 

 not only with the ordinary arithmetical lessons, but also 

 with the actual details of daily life. Nevertheless the 

 general impression conveyed is disappointing. .A prefatory 

 memorandum warns the reader that the committee re- 

 garded as outside its purview the discussion of the functions 



