TRANSACTIONS OF SECTION D. 547 
The kangaroo and camel each have translucent roof and sides of skull 
(except in region of horns), so has the seal. The parietal in part is translucent 
in both manattee and dugong. The upper surface of the skull in dogs is not so 
translucent as the sides. The dolphin’s skull is opaque above and translucent 
behind, and at the central part of sides. The proliferation of the bone cells along 
muscle attached appears to co-exist with the diminution of the bone under brain 
and muscle pressure. The bone cells, like Jeucocytes, desire to avoid the centres 
of turbulent activity. . 
The skull of the porcupine is translucent over the frontal and parietal; the 
capybara has a skull that is translucent on each side of the middle line in front of 
the roof, and also at the posterior part of the roof, where the translucency is 
strictly limited to the upper surface. It is sometimes stated that the portions of 
the skull covered by muscle (or ‘ protected’) are thin. The suggestion is that the 
skull is strengthened where most exposed. It seems better to refer the thinning 
to the pressure of the muscle mass, brain, or organ. The ridges are due to the 
accumulation of bone-forming tissue at the points of origin and insertion of the 
muscles in question. The skull does not appear to lose, but to gain, in strength 
by the groining (J. Hunter and Holden). The osteoblasts, like leucocytes, seem to 
avoid the places where thrills or shocks are most common. The former have 
greatest freedom outside the active centres, as the latter in the least disturbed 
nooks contribute to the formation of fibrin. 
6. Joint Discussion with Sections K and L on the Teaching of Biology 
in Schools, Opened by OswaLp H. Larter. 
The right of biology to rank as a subject in general education is now 
generally conceded and its merits recognised. As a training in experiment, in 
precision, and in exact reasoning it perhaps has not the advantages of physics 
and chemistry; but in quickening the powers of observation it is unsurpassed by 
any of the sciences. Moreover, it deals with phenomena which perforce must 
come before every man in the daily concerns of occupation and leisure, and 
on which indeed his very existence depends. The laboratory and all its para- 
phernalia are not always necessary for its pursuit. 
Of the two biological subjects, zoology and botany, the former will receive my 
attention, rather at the request of those responsible for summoning this conference 
of Sections than because I attach superior importance to the subject in which 
I chance myself to have been trained. Twenty years’ experience as a teacher has 
convinced me that were I constrained to teach only one biological subject my 
choice would fall upon botany for purposes of general education. 
At what age, then, (1) should the study of zoology begin? (2) Along what 
lines should it be pursued ? And what relation should this subject bear to the 
other sciences which find place in curricula? (8) How far may we proceed into 
zoological principles and philosophy ? These questions apply to class teaching and 
not to those special divisions—elementary technical sets—which are for the most 
part composed of embryo medical students. 
(1) Living animals present great attractions to and deeply interest the minds 
of quite young children. ‘hus there is the ample justification of Nature’s own 
authority for a very early commencement. In the preparatory school and lower 
forms ot public schools the standard indicated by the term ‘nature-study’ is 
undoubtedly the very best form of science training. When applied to animal- 
study this resolves itself into observation of habits and life-histories, methods of 
locomotion, of feeding, and perhaps of breathing; noting of the external form 
and its special adaptations to the circumstances of life. It is essential that each 
pupil shall learn as the result of direct personal observation; mere reading and 
lectures, except that they may arouse some interest, are of no value. Assuming, 
then, that each pupil is provided with living specimens, the guidance of the 
teacher is needed to direct the attention to the important features. And here it 
is important to avoid doing too much. The guidance afforded should consist of 
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