158 



Hutchison (R. H.). Overwintering of the House Fly.— JZ. Agric. 

 Research, Washington, D.C., xiii, no. 3, 15th April 1918, pp. 149- 

 169, 1 plate. 



Experiments and observations on the method of over- wintering of 

 the house-fly, Musca dotnestica, L., have shown that it cannot pass 

 the winter in the adult state when exposed to outdoor conditions, 

 nor when in heated buildings, where it is particularly liable to attack 

 by the fungus, Empusa muscae. It may be kept alive much longer 

 in such places as attics and stables that are only slightly heated. 

 Experiments ^ith the house-fly do not support Dove's theory, based 

 on experiments with Lucilia sp., that the fungus, E. muscae, develops 

 principally in sexually mature and fertilised flies, which do not oviposit 

 on account of low temperatures or the absence of suitable media for 

 their eggs. In the latitude of Washington, D.C., M. domestica may 

 over-winter from November to April in two ways : — (1) by continued 

 breeding in warm places where food and breeding-places are available, 

 the individuals present in March and April being the offspring, and not 

 the survivors, of those present in autumn ; (2) in the larval and 

 pupal stages in or under large manure heaps ; though whether this 

 method of over- wintering or that by continued breeding is the more 

 common or successful cannot now be stated. Judging from the fact 

 that flies do not appear in large numbers till late in May or early in 

 June, it is probable that only a very small percentage of the larvae 

 present in manure heaps in autumn live through the winter and 

 give rise to adults in the spring. 



On the other hand it is probable that the method of over-wintering 

 by continued breeding is much more wide-spread than is now reahsed, 

 especially in cities, where there must be numerous foci, such as 

 kitchens, dining-rooms, restaiftants, bakeries, animal houses and the 

 like, from which flies escaping on warm days in March and April 

 survive to produce the hordes that begin to appear in May. 



Kesearch has shown that M. domestica does not exhibit any 

 retardation of ovarian development such as that met with in Pollenia 

 rudis, in which the ovaries remain undeveloped until spring, and which 

 hibernates in the adult state, being able to withstand the effects of 

 considerable cold. 



Lebceuf (A.) & Gambier (A.). Sur deux Cas de Spiroch6tose humaine 

 observes a Brazzaville (Moyen-Congo). [On two Cases of Human 

 Spirochaetosis observed at Brazzaville (Middle Congo).] — Bull. 

 Sac. Path. Exot., Paris, xi, no. 5, 8th May 1918, pp. 359-364. 



This paper records chnical observations on two cases of human 

 spirochaetosis, due presumably to Spirochaeta duttoni, the symptoms 

 observed being characteristic of relapsing fever. 



Chatton (E.) & Blanc (G.). Large Eclectisme parasitaire de la 

 Punaise des Lits. Son Entretien aux Depens des Reptiles. [Wide 

 Choice of Hosts by the Bed-bug. Its Maintenance on Reptiles.] 

 —Bull. Sac. Path. Exot., Paris, xi, no. 5, 8th May 1918, 

 pp. 382-387. 



There are three species of the genus Cimex or its allies that 



