326 



NATURE 



[May 29, 1913 



The classical account of the pagan tribes of the 

 Malay Peninsula by Messrs. Skeat and Blagden is 

 being gradually supplemented by later inquiries 

 among this interesting people ; but these investiga- 

 tions only serve to prove the correctness of the earlier 

 record. Mr. L. H. N. Evans now publishes in the 

 Journal of the Federated Malay States Museum, which 

 takes the place of the Perak Museum Notes, an 

 account of the Besisi of Tamboh, Kuala Langat, 

 Selangor. Their advance in culture is illustrated by 

 the fact that they are now able to ride bicycles, which 

 they borrow from the Chinese. Mr. Evans made a 

 considerable ethnographical collection, including 

 specimens of two methods of fire-making — by the saw 

 and drill — which are being replaced by the use of 

 matches and the flint and steel. As an example of 

 culture contact, two ingenious forms of animal traps 

 are now found in use from Nepal and Assam eastward 

 through Indo-China and the Malay Peninsula, and all 

 over the Greater Sunda Islands. 



The researches that are being carried out at the 

 present time, with so much patience and minuteness, 

 upon disease-producing parasites, though undertaken 

 primarily with practical aims in view, are helping to 

 accumulate in many cases data of great value from a 

 purely scientific and theoretical point of view. It is 

 becoming, for example, increasingly evident that the 

 pathogenic trypanosomes represent a group of in- 

 cipient species in process of coming into being, in 

 many cases differentiated physiologically, but not 

 morphologically. From this point of view the human 

 trypanosome generally known as Trypanosoma 

 rhodesiense is very interesting. It is possible that it 

 is an old-established species lately discovered ; but it 

 is far more probable that it has become but recently 

 differentiated, and that it represents either a race of 

 T. brucii that has acquired the power of living in 

 human blood, or a race of T. gambiense adapted to 

 transmission by Glossina morsitans. The former view- 

 has been advocated by Bruce and his colleagues, of 

 the Royal Society's commission working in Nyasa- 

 Iand ; but Stephens and Fantham, in a paper in the 

 Annals of Tropical Medicine and Parasitology (vol. vii., 

 No. 1), find it difficult to distinguish between T. 

 rhodesiense and T. gambiense by means of measure- 

 ments. The chief distinctive character of T. 

 rhodesiense is the presence of the so-called posterior 

 nuclear forms, which are studied by Blacklock in a 

 memoir in the same journal ; these forms have been 

 found, however, in other species of trypanosomes, in- 

 cluding T. brucii. ' 



We have received a report by Prof. E. C. Starks, 

 issued in the Leland Stanford Junior University Pub- 

 lications, on the fishes collected by the second Stan- 

 ford expedition to Brazil, in which several species 

 are described as new. A report has also reached us 

 on the fishes of certain tanks in Bengal, drawn up 

 by Mr. T. Southwell and Capt. R. B. S. Sewell, and 

 published at Ranchi by the Bihar and Orissa Depart- 

 ment of Agriculture. 



The March issue of the Proceedings of the Phil- 

 adelphia Academy contains a report on parasitic worms 

 infesting the animals in the local zoological gardens. 

 NO. 2274, VOL. 91] 



The average number of infestations is about forty-five 

 per annum, but in 1910 there was a rise, due to the 

 prevalence of cestodes in birds, while a second rise, 

 owing to nematodes in parrots and perching birds, 

 occurred in the following year. Among mammals 

 Carnivora are much more heavily infested than any 

 other order, monkeys, ungulates, and marsupials 

 making nearly a dead-heat for second place. The 

 new observations confirm previous statements that 

 nematodes are the most common parasites, these being 

 followed by cestodes, flukes, and Acanthocephali, in 

 the order named. 



In The American Museum Journal for March Mr. 

 Barnum Brown describes, with a good series of photo- 

 graphs, the discovery at Red Deer River, Alberta, of 

 a new crested dinosaur, now named Saurolophus, "the 

 crested saurian." In life this animal was about 32 ft. 

 in length, and stood about 15 ft. in height when 

 erected. Like Tracodon, it was a herb-eater, and 

 unable to defend itself from the contemporary flesh- 

 eating Albertosaurus, except by its po\ver of escaping 

 danger by swimming. Great numbers of these 

 creatures lived in the prehistoric coastal marshes, and 

 in a single quarry on the Red Deer River bones of 

 several hundred individuals, mostly of this kind, have 

 been washed out of the bank. Another set of bones 

 discovered in the same district represents the skeleton 

 of another new dinosaur coming from an older forma- 

 tion, and probably an ancestor of Saurolophus. 



The first of a series of studies on the evolution of 

 the teeth of primates, by Dr. L. Bolk, professor of 

 anatomy in the University of Amsterdam, has been 

 published (G. Fischer, Jena, 1913, price 5 marks). A 

 completely new interpretation is given of the relation- 

 ship between milk and permanent teeth. We have 

 hitherto regarded them as belonging to different 

 epochs of evolution — the milk teeth representing a 

 primary dental outfit, the permanent a secondary 

 acquisition. Prof. Bolk, from a prolonged inquiry 

 into the developmental stages of the teeth of reptiles 

 and mammals, has accumulated evidence to show that 

 both reptiles and mammals have arisen from a stock 

 which was furnished with three rows of teeth, all of 

 which came into use at the same time. In both 

 reptiles and mammals the outer row is represented 

 by vestiges — the so-called pre-lacteal dentition. In 

 reptiles the middle and 4nner rows persist and come 

 into use together. In the higher or diphyodont mam- 

 mals the middle rows come into use first, forming 

 the milk dentition, while the inner is delayed in its 

 appearance, and forms the permanent set of teeth. 

 In lower or monophyodont mammals both middle and 

 inner rows of teeth — that is to say, milk and per- 

 manent teeth — come into place and use together, 

 forming an apparently linear series. Prof. Bolk's 

 hypothesis promises to simplify our conception of the 

 evolution of mammalian teeth, and explains many 

 facts which were formerly obscure. 



Mr. W. Engelmann, Leipzig, has lately issued 

 parts 55,56, 57, and 5S of "Das Pflanzenreich." This 

 magnificent regni vegetabilis conspectus is making 

 rapid progress, though up to the present time only 

 one group (Sphagnaceae) of cryptogamous plants has 



