Jakuary 1 6, 19 1 3] 



NATURE 



549 



was delayed with trouble over his dogs, and those he 

 obtained appear to have done him but poor service. 

 Much additional labour devolved upon himself and his 

 companion, Iversen, who made the journey to Dan- 

 marks Fjord, and they had to struggle as well against 

 privation, and, from time to time, sickness. They 

 were in large measure dependent on caches of pro- 

 visions, the contents of which might or might not 

 prove sufficien.t for their needs, and on obtaining 

 game, the appearance of which was problematical. 

 Captain Mikkelsen outlined his discoveries relating to 

 the important work of the Mylius Erichsen expedition, 

 as it was his main object to recover the records of 

 the lost leader and his companions, Bronlund and 

 Hoeg-Hagen. He was successful, and referred to the 

 serious import to his own plans of the report left by 

 Erichsen of the non-existence of the Peary channel. 

 This channel Mikkelsen had intended to follow to the 

 north-west coast. By his experiences of boat-work 

 among the ice, and of journeying over the sea and 

 inland ice, and coastwise, Mikkelsen has added com- 

 prehensively to our knowledge of the conditions of 

 travelling in Greenland. 



M. .\. Prazmowski contributes a second study on 

 the nitrifying organisms of the group Azotobacter in 

 the BuW. Internal, de I'Acad. des Sciences de Cracovie 

 (Xo. 7B, July, 1912). Azotobacter is a true Schizo- 

 mycete, though it has affinities both with the protozoa 

 and with the unicellular algae. Its pre-eminent func- 

 tion is to fix nitrogen, and it is probable that it can 

 obtain nitrogen either from nitrogenous compounds or 

 from the free nitrogen of the atmosphere. 



Malaria is prevalent in the Andaman Islands, Bay 

 of Bengal, and a valuable report on the subject has 

 been furnished by Major Christophers (Scientific 

 Memoirs of the Government of India, No. 56, 1912). 

 The chief carrier in the settlements is the anopheline 

 mosquito Nyssomyzomyia ludlowi, a species which 

 breeds in and about salt swamps, and was not found 

 at a greater distance from salt or brackish water than 

 half a mile. It was proved to carry the malignant 

 tertian parasite, and it is quite probable that it carries 

 all forms of the malaria parasite. 



Dr. Wielowiejski has directed our attention to an 

 article by Prof. Hofer in the Osterreich. Fischerei 

 Zeitung (No. 21, 19 12) on the biological purification 

 of sewage effluents, &c., by means of fish. Tanks 

 have to be provided, in extent at the rate of one 

 hectare (2^5 acres nearly) per 2000-3000 persons. 

 They work w-ell even in winter, when covered with 

 ice, and are quite equal in efficiency to irrigation in 

 sewage farms, and financially the return is better 

 than from sewage farms, as 500 kilograms of fish 

 (carp) are reared per hectare (in what time is not 

 stated). 



In spite of the enormous and rapidly increasing 

 output of zoological literature at the present time, it 

 is surprising what a large number of well-known 

 types, constantly studied by students in the labora- 

 tory, remain inadequately described. A good general 

 account of the morphology of such forms is always 

 NO. 2255, VOL. 90] 



valuable, even if it be restricted to some particular 

 system of organs, and we welcome the appearance in 

 the Zeitschrift fiir wissenschaftliche Zoologie of two 

 monographs of this kind. The description by Rudolf 

 Hillig of the nervous sytem of Sepia officinalis {op. 

 cit., vol. ci., part 4) is a detailed and admirably illus- 

 i trated piece of work, which cannot fail to be widely 

 ; useful, though we fear that but few students will be 

 able to find time to follow it out in all its intricacies. 

 The same remarks apply with equal force to the more 

 comprehensive account by Erich Reupsch of the 

 anatomy and histology of the common Heteropod, 

 Pterotrachea coronata {op. cit., vol. cii., part 2). 



Two notable monographs on the invertebrate fauna 

 of Japan have recently been published in the Journal 

 of the College of Science, Imperial University of 

 ! Tokyo. The first (vol. xxx., art. 2) is on "The 

 Errantiate Polychaeta of Japan," by A. Izuka, and con- 

 tains a systematic account of the group illustrated by 

 twenty-four plates. The term " errantiate," instead of 

 "errant," strikes us as being somewhat peculiar, and 

 we do not remember to have seen it before. The 

 second (vol. xxix., art. 2) is a posthumous work on 

 the actinopodous Holothurioidea, by the late Prof. K. 

 Mitsukuri, whpse death was such a grievous loss to 

 zoological science. This work has been edited by 

 Prof. I. Ijima and Mr. H. Ohshima, and is illus- 

 trated by admirable text-figures of the calcareous 

 skeletal elements and plates of external form. The 

 coloured illustrations, drawn from life, are very beau- 

 tiful, and for quaintness of form and colour it would 

 be difficult to find any invertebrate to surpass 

 Enypniastes eximia. 



Observations made on Long Island at the be- 

 ginning of June, 1911, have enabled Dr. L. Hussahof, 

 in The American Naturalist for December, 1912, to 

 obtain new information with regard to the breeding 

 habits of the sea-lamprey {Petromyson marinus). It 

 has been considered that fertilisation in these lampreys 

 is internal — a supposition which may be explained by 

 the fact that the eggs can develop parthenogeticall}', 

 but in ordinary cases normal fertilisation takes place. 

 Both this formation and spawning occur in a kind of 

 nest made in the bed of a stream by carrying awa}' 

 stones in the circular sucking mouth until a basin- 

 shaped depression is formed, on the bottom of which 

 sand accumulates. Like eels, lampreys never return 

 to the sea after spawning. Death appears to be 

 mainly due "to the cycle of metabolic processes initiated 

 on the maturing of the gonadial products " ; but this 

 may be aided by reduced vitality due to the labour of 

 removing stones from the nest, and also by the 

 development of " fungus " in the self-inflicted wounds 

 made during the breeding season. 



The determination of the magnitude of the experi- 

 mental error in agricultural field trials has recentiv 

 attracted considerable attention in this country, and 

 has now been investigated in the United States by 

 I Prof. Lyttleton Lyon, of Cornell. The results are 

 j published in the Proceedings of the American Society 

 of Agronomy, and afford interesting confirmation of 

 I those obtained at Rothamstcd and at Cambridge. 



