56 



in children and in dogs, and the close relations of contact between 

 children and dogs affected with leishmaniasis and fleas affected with 

 parasitic Protozoa that are morphologically and biologically indis- 

 tinguishable from Leishniania, tend to prove that visceral leishmaniasis 

 of the Mediterranean is produced by a species of Herpetomonas of 

 Pulex irritans and Ctenocephahis canis that has adapted itself to 

 live in children and dogs, themselves the habitual hosts of these 

 fleas. 



Carter (H. F). Descriptions of the Adult, Larval, and Pupal Stages 

 of a New Mosquito from Lord Howe Island, S. Pacific.— P^oc. 

 Zool. Soc, London, 1920. pt. 4, December 1920 pp. 623-628, 

 3 f^gs. 

 I.,arvae and pupae of Ochlerotalits laiirci, sp. n., here described, 

 were taken from a hollow in a fallen tree-trunk containmg water. 

 Adults of another species of Ochlerotatiis were taken in a dwelling- 

 house at night. 



Parkinson (W. H.) & Bell (H. D.). Insect Life on Sewage Filters.— 



London, The Sanitary Publishing Co., Ltd., 1919, viii+64 pp. , 

 8 figs. [Price 3s.] [Received 24th February 1921.1 



This useful work deals with a Collembolan, Achorutes viaticm, L. 



In 1910 the junior author found this springtail (then erroneously 

 called Podura aqiiatica) playing an important part in sewage purifica- 

 tion at the Corporation Sewage Works, Straff ord-on- A von, where 

 " ponding " has since been entirely eliminated as a result of its presence. 

 Sewage filters containing this Podurid maintain high nitrates, and 

 produce high percentage purification of the tank effluent. The con- 

 clusion drawn from experiments, a description of which forms the 

 major portion of this little volume, is that A. viaticus does contribute 

 to the production of ammonia and carbon dioxide, either by passing 

 air upward through a liquid containing sewage, as in the " activated 

 sludge " process, or by its action on growths deposited by tank effluent 

 in sewage filters. 



A description of this species, its habits, distribution, food, and classi- 

 fication, is taken from Wilson and Johnson's work, " Organisms Found 

 in Sewage Filters." A. viaticus measures about 2 mm. in length. 

 About 9^000 weigh 1 gramme, or 4,000,000 to the lb. Though the name 

 Achorutes (" not dancing ") suggests lack of activity, this species can 

 show considerable vigour, especially in warm weather. It occurs 

 generally in connection with decaying animal or vegetable matter, 

 and has been recorded from Norway, Siberia, Denmark, Britain, 

 Greenland, South America, and in islands south of New Zealand. 

 It has appeared spontaneously at various sewage works in Great 

 Britain, and has been introduced on others. Its chief food is the 

 colloidal growths that separate out from sewage on any rough surface. 

 It also feeds on the larvae of Psychoda, a sewage fly that is a serious 

 nuisance at some works [cf. R. A.E., B, vii, 24, 90]. 



It is not yet possible to state why A. viaticus abounds on some 

 sewage works and is absent on others. 



