10 



KNOWLEDGE ♦ 



[JuNli 



Cnrrant Moth {Ahraxas Grossvlariata), together with 

 many others, may be fonnd in the bogiuniD^ of this month. 



Several of the CfsPiPAT.t nro now out, the Puss Moth (Cerui-a 

 I'l'nicJa) and ilio Pcbblo Prominent {^Xotodonta Ziezac) being most 

 common. 



A great number of the ?\ocTi'.Earo now on the wing. Among them 

 we mav expfct to find the following :—Tl>e Alder (Acronijcta Alni), 

 the Bramble (.4fr.iiiy.-((i Riimifi'*), Common Wainscot {Leucania 

 Pallrnn), Bird's Wing (Diptenigia Pinagtri), Doubtful Nutmeg 

 (Uaimstra Anceps), Cabbage Moth {ifamesira, Braissicce) , lYoblo 

 Lines(Gr.immi;»i.i2'iiIiHea),DoubleS(iuareSpot(A"'oc(ua3Viaii<;itIum), 

 Ac. These, and several others more or less scarce, aro to be 

 obtaine<l during the beginning of the month, but success depends 

 in a great measure on weather and other extraneous circumstances. 



In all cases I have given, and shall continue to give, the Latin 

 names together with the English, the former beingmost important. 

 The first Latin n.-»me shows to what family the insect belongs, the 

 second the specific name is used only for that particular indi- 

 ridual. The specific name must be l'>arnt together with the 

 English, as genuine collectors invariably employ the former when 

 speaking of a butterfly or moth, the advantage being that many 

 insects have purely local names, and an entomologist from, say, the 

 south of England, would find the same insect called by a very dif- 

 ferent English name in the north country-, but tho Latin appella- 

 tion is the same all over the world. 



A great many caterpillars are to be found this month on the 

 trees and hedges, and next week we will give a short list of them, 

 together with their haunts and food. If the lepidopterist comes 

 across any in the course of his travels he would do well to box 

 them together with a piece of the tree on which they are feeding, 

 and breed them up. A hat-box with a piece of net stretched over 

 the top acts as a fair elementary breeding-house, but next week wo 

 will describe the manner of making a good one. Feed the eater- 

 pillar once a-day with fresh leaves, but do not liandle them, as 

 they are very delicately organised, and a slight squeeze might do 

 them considerable injury. 



MASS AND WEIGHT OF THE BRAIN. 



IX his able treatise, entitled " An Introduction to Human 

 Anatomy," Professor Turner, of the University of Edinburgh, 

 writes thus on ''The Mass and Weight of tho Brain" : — 



The human brain is absolutely bigger and heavier than the 

 brain of any animal, excepting the elephant and tlie larger whales. 

 The brain of the elephant is said to weigh from 8 lb. to 10 lb., and 

 that of a large finner whale between 5 lb. and 6 lb. The human 

 brain is also heavier relatively to tho bulk and weight of 

 the body than are the brains of the lower animals, except 

 in some small birds and mammals. Considerable variations, 

 however, exist in the size and weight of the human brain, not only 

 in the different races of mankind, but in individuals of the same 

 race and in the two sexes. The heaviest brains occur in the white 

 races. The average weight of the adult European male brain is 

 ■ICioz. to 50 oz. (about 3 lb.), that of the adult female 'Woz. to'ISoz.; 

 BO that the brain of a man is, on the average, fully 10 per cent, 

 heavier than that of a woman. Tlie greater wciglit of the brain in 

 man, as compared with woman, is not in relation merely to his 

 greater bulk, but is a fundamental sexual distinction ; for, whilst 

 there is a difference of 10 percent, in the brain weiglit, the average 

 stature of women is, according to Thurnam's calculations, only 8 per 

 cent, less than that of men.* 



Or. Boyd states that the average weight of tho brain in tho 

 newly-bom male infant is 11-67 oz. ; in the female only 10 oz. Tho 

 exact a'/e at which the brain reaches its maximum sizo has been 

 variously placed at from tho third to tho eighth year by different 

 authors ; but it continues to increase in weight to 25, or '.iO, or even 

 ■U). After CO the brain begins to diminish in weight ; in aged 

 males the average weight is about 45 oz. ; in females about 41 oz. 



In some cases the adult brain considerably exceeds the average 

 weight. The brains of several men distinguished for their intellec- 

 tual attainments have been weighed. The brain of Cuvior weighed 

 01} oz. ; of Dr. Abcrcrombic, C3 oz. ; of Professor Goodsir, .57i oz. ; 

 of .Spnrzheim, 55 oz. ; of .Sir J. Y. Simpson, 51-oz. ; of Agassiz, 

 .'>3-4 oz. ; and of Dr. Chalmers, 53 oz. But high brain weights have 

 been found where there was no evidence of great intellectual 

 caf^acity. Peacock weighed four male brains, which ranged from 



[• If thi.i is so, tho brains of women aro more mussive relatively 

 than those of men, for the weight varies, cmlerin •paribut, as the cubo 

 of tho height, so that the weight of woman is less than that of man 

 by 92 cnbed, as 778688 U less than 1,000,000, or by more than 22 per 

 cent.— Ed.] 



62-75 oz. to 61 oz.; Boyd, a specimen of eO-7r)or ; and T have in 

 my possession ono of a boy, aged \^. v, ! irli •■ ■■ ! il ''•" (v Tn tho 

 brains of the insane, high brain w^i ! : ' ^ ' rvod. 

 Bucknill met withabrain in aniali' 1 I I I > i illuz. ,• 

 Thurnam one which weighed G2 oz. ; aii.l M \\. I I, iiliM Asylum, 



out of 375 males examined, the weii^lit ul I lie liiain iii au cases was 

 55 oz. or upwards, and tlie highest weights were 6 1 oz . in a case of senile 

 dementia, 60i oz. in a case of dementia, and 00 in a case of melan- 

 cholia. No ease has as yet been recorded of the weight of the 

 brain in a woman of great intellectual uttainnients ; but Boyd met 

 with a woman's brain as high us 5525 oz., and many instances of 

 upwards of 50 oz. in women where there was no evidence of high 

 mental endowment. Skae, in a female monomaniac, observed a 

 brain which weighed 61i oz. ; and of 300 females examined in the 

 West Hiding Asylum, tho weiglit of tho brain in 26 cases was 50 oz. 

 or upwards, tho highest weights being 56 oz. and 55 oz. in two 

 cases of mania. 



The size and weight of the brain do not, therefore, per so, givo 

 an exact method of estimating the intellectual power of the indi- 

 vidual, and a high brain weight and great intoUeetual capacity aro 

 not necessarily correlated with each other. 



TOO MUCH BRAIN-WORK. 



" r\^ April 28, Dr. l{i.;hardson, F.H.S., delivering a lecture on 

 \J ' National Necessities as the Bases of Natui-.il Education,' 

 before the Society of Arts, brought forward," writes P.C.S., "tho 

 following extract, which hajipenod to lie a report of the Chairman 

 of the evening, Mr. Edwin Chadwick, CIS., to the British Associa- 

 tion in 186n, to show what an evil otTect too much brain-work, 

 without a prnpnrtiniinl nTiionnt of industrial occupation to support 

 it, has 11)1011 \niiiiL' .Iiillivii. I givo the extract vorhatim,a.a it 

 bears closely (ill a |iciini i-.i-nitly under discussion : — 



" In oni' lar-r isiaMisliiaent, "containing about .<.i\- liiuulrod chil- 

 droii, half -iris ami half boys, tho means of i-pln liiil .irnipation 



wc-ip f.'aiiH'd fur tlu' t;irLs before any were nlii ii- I i.i lioys. 



'Chr ;.'irls wci-c tlicivfon^ lint upon half-time I in: msay, 



llieir (iino of book-in.Htnictioii was reduced iiMin iniiy i. hours to 

 eighteen per week, given on tho three altcrnalu days of tlieir in- 

 dustrial occupation, tho boys remaining at full school time of thirty- 

 six houi-s per week, the teaching being the same, on tho same 

 system, and by the same teaelieis, the same school attendance in 

 weeks and years in both cases. On the periodica! examination of 

 the school, surprise was expressed by the inspectors at finding how 

 much more alert, mentally, tho girls were than tho boys, and in 

 advance in book attainments. Subserpiently, industrial occupation 

 was found for the boys, when their time of book instruction was 

 reduced from thirty-six hours a week to eigliteen ; and after a 

 while, the boys were proved, upon examination, to have obtained 

 their previous relative position, which was in advance of the girls." 



BRAIN TROUBLES. 



IlIAVE carefully read " Brain Troubles," and have met with 

 many changes which might seem alarming to one who knows 

 not the influence of digestion on the mind. The cases I am now 

 going to give aro due to indigestion or some irritation of the 

 stomach on the controlling powers of tho brain. After a heavy 

 meal, especially after a heavy breakfast, 1 find some of my patients 

 cannot write proper English. They say they can express their 

 thoughts, but not in proper style. Other times they cannot 

 express them at all. If they try to do so, they find they have 

 forgotten half of their subject. If they continui; to write in 

 spite of this, they i-uii words into each other. Thus, in writing 

 " other rogues," they put down " other oguee," and often 

 drop a word out of the sentence. Sometimes they mis-spell 

 a word, know that it is wrongly spelt, and yet cannot find out tho 

 mistake, unless they consult a "dictionary. The same in adding up 

 a sum, or multi]jlying ; when they come to prove a sum they find it 

 wrong, yet cannot find out where the iniHtiike is for a time. They 

 may change letters in different words, thus in writing " good boy" 

 they may put down "goob doy." Tliere aro other little things 

 which an observer may notice, and which aro not signs of brain 

 troubles, but of indigestion, or of some improper material in tho 

 blood giving rise to these symptoms. These are not usually seen 

 before a meal, or after a light on('. 



Again, irritaljility of temper most often means indigestion, or too 

 full bloodvessels. Whenever I feel vexed at any trifling annoyance, 

 1 know I am suffering from too much food. I go for a walk or take 

 some exercise, and so got rid of my spleen ! I hope this may bo 

 taken in its true light, and not as a criticism on "Brain Troubles." 

 T. R. Allinson, L.R.C.P., &c. 



