740 



SCIENCE 



[N. S. VcL. SXVII. No. 697 



correct in itself), surely in this connection 

 should at least be mentioned the suggestive 

 observations of Charles Hill as to the eleven 

 neuromeres in teleosts and birds. 



Fig. 149 — Unless otherwise stated, a " longi- 

 tudinal " section is assumed to be mesal. or 

 sagittal and parallel vpith the meson, or at 

 least in one and the same plane. Here the 

 cerebral and olfactory regions are not in the 

 same plane with the rest. No one would be 

 more pleased than the reviewer to find a brain 

 with a single olfactory tract and bulb on the 

 middle line as — in the absence of qualification 

 — is the case in this figure, the " ideal " key to 

 the " real " brains that follow it. The dotted 

 ellipse marked Tho (" optic thalamus ") might 

 fairly represent the midcommissure connect- 

 ing the two thalami, but hardly those bodies 

 themselves; see also under Fig. 152. 



Fig. 150 — In neither the original nor the 

 adaptation is it stated what brain serves as 

 the basis of this diagram. 



Fig. 151 — Here are five diagrams " illus- 

 trating the structure of the hypophysis " 

 (pituitary body). They are not adequately 

 explained in either the general text or the 

 description, and the latter contains words, 

 " chromophilous " and " chromophobic," which, 

 like " chromafiin " (pp. 495-6) are neither de- 

 fined nor included in the index. Even orien- 

 tation of these diagrams is difficult since more 

 complete figures with which they might be 

 compared (150, 154, 161, 165, 172) head in 

 the opposite direction. 



Fig. 152 — This diagram of the " ventricles," 

 as if their roofs were removed, should be co- 

 ordinated with Fig. 149. Here the side walls 

 of the ■" third ventricle " might properly be 

 designated thalami. 



Fig. 153 — In a diagram to illustrate the 

 several flexures of the brain there is perhaps 

 no great harm in representing the midbrain 

 as if it were a flattened " lump " suggesting 

 no organic relation with the adjoining seg- 

 ments. This figure, or some other, should 

 exhibit the definite topographic relation of the 

 principal (mesencephalic or cranial) flexure 

 to the cephalic end of the notochord. 



Figs. 157 and 158 — To these representations 



of the dorsum, venter, left, and exposed cavi- 

 ties of a shark brain should have been added 

 a midsection. The foramen so conspicuous 

 on the venter is not named or even accounted 

 for in the description or text; yet, as figured 

 and described by the reviewer in 1876 {Amer. 

 Jour. Science, Vol. 12, pp. 103-5) it is very 

 significant in connection with the embryonic 

 condition with most sharks and the permanent 

 condition of the more primitive forms. 



Fig. 159 — From this brain of the gar, as 

 usual with ganoids and teleosts, the telas are 

 omitted, and their absence is hardly accounted 

 for with sufficient clearness in the text. More 

 serious is the lack of qualification respecting 

 the interpretation of the cephalic portion. It 

 is probable that the conditions are essentially 

 the same as in the Teleosts with sessile ol- 

 factory bulbs, viz., the wider pair of solid 

 lobes marked prs. are the striata, the smaller 

 ones beyond (hollow in ganoids but practically 

 solid in teleosts), the olfactory bulbs, and the 

 so-called olfactory lobes merely the slightly 

 enlarged beginning of the nerves. It is a re- 

 proach to the comparative anatomists of this 

 country that the brain of this exclusively 

 American form should not have been fully 

 elucidated. The reviewer frankly accepts his 

 share and admits the erroneousness of certain 

 interpretations of 1875 (A. A. A. S., Proceed- 

 ings, p. 179 and pi. 2) ; but in respect to the 

 then prevailing non-recognition of the " mor- 

 phological importance of the membranous or 

 other thin portions of the parietes of the en- 

 cephalic cavities " he made a general con- 

 fession and promise of reform in a paper 

 under the title quoted above, read before the 

 Association of American Anatomists and pub- 

 lished in the Journal of Comparative Neurol- 

 ogy, October, 1891, pp. 201-3. 



Fig. 163 represents the dorsum of the brain 

 of Ceratodus (Neoceratodus), taken by the 

 adapter (unaccountably the author gives no 

 dipnoan brain) from Parker and Haswell's 

 "Zoology." In that work it is said to be 

 " chiefly from Sanders " ; it is defective in 

 several unspecified respects and bears no close 

 resemblance to the only figure by that anat- 

 omist known to the reviewer, viz., in the 



