G12 SUMMARY OF CURRENT RESEARCHES RELATING TO 



substance whose accumulation leads to the muscular movements which 

 precede awakening. He refers to the similarity between his theory, 

 stated in 1886, and that of Lcgendre and Pieron (1911), who find 

 evidence that when sleep is prevented there accumulates in the blood a 

 narcotic substance inducing sleep when injected into other animals. 



Sense of Direction in Blind.* — Truschcl has made a large number 

 of experiments in regard to the sense that blind people have of a near 

 object, or of an object which they approach. The result of his experi- 

 ments is to suggest that the perception is auditory, the near object 

 reflecting and altering surrounding sounds. To the objection that a 

 deaf-mute is said to have exhibited the sense, the author answers that 

 those quite deaf to music and speech are sometimes sensitive to very 

 feeble noises. 



Plica semilunaris in Hereros and Hottentots. f — Paul Bartels has 

 followed up the discovery of Giacomini, who showed that the plica semi- 

 lunaris conjunctivae in coloured races has often a minute piece of carti- 

 lage, the occurrence of which is one of the greatest rarities among white 

 folk. The plica is a representative of the so-called third eyelid (in whole 

 or in part) of mammals, birds and reptiles. The presence of the cartilage 

 shows that the Hottentots are pro tanto more theromorphic than whites, 

 for it is present in all monkeys. 



Bartels studied 8 Herreros and 17 Hottentots, and found the little 

 piece of cartilage in 12 ; Giacomini found it in 12 out of 16 ; Adachi 

 found it in 5 Japanese out of 25 ; Giacomini found it 4 times in 548 

 whites ( = • 73 p.c.) 



Vertebrate Lower Jaw.J — E. Gaupp discusses the " gonial," a mem- 

 brane bone of the lower jaw, which is usually penetrated by the chorda 

 tympani. It is the " angular " of some amphibians ; it fuses with the 

 articular in lizards and some amphibians ; it is the processus anterior 

 mallei in mammals. The malleus is indeed a gonio-articular. 



Mammals of West Indies.§ — Glover M. Allan has studied these in 

 relation to the problems of geographical distribution. It appears that 

 the present evidence afforded by the distribution of West Indian mammals 

 in the main corroborates the current hypothesis that the fauna is derived 

 in part from northern South America, and in part, by means of probably 

 at least two land bridges, from North and Central America. 



Digestive System of Hornbill.|| — H. C. Curl has made sections of 

 the various parts of the gastro-intestinal tract of Hydrocorax hydrocorax. 

 He has particularly studied the deciduous membrane lining the stomach, 

 which is periodically ejected with undigested refuse. The deciduous 

 membrane is a tough homogeneous secretion from the glands of the 

 stomach. About the position where one would expect caeca, the mucous 



* Cornptes Reudus, clii. (1911) pp. 1022-4. 



t Arch. Mikr. Anat., lxxviii. (1911) Festschrift Waldeyer, pp. 529-64 (1 pi. and 

 1 fig.). % Anat. Anzeig., xxxix. (1911) pp. 97-135 (16 figs.). 



§ Bull. Mus. Comp. Zool. Harvard, liv. (1911) pp. 175-263. 

 j Philippine Journ. Sci., vi. (1911) pp. 31-6 (2 pis. and 1 fig.). 



