199 



of larvae had dropped. After the beast had been fed and lain down 

 the dropping of the larvae ceased and recommenced when the beast 

 got up. It would thus appear that there is some connection between 

 the movements of the animal and the dropping of the larvae and 

 probably the reason is purely mechanical and due to varying tension 

 of the skin produced by these movements. The next question enquired 

 into was the number of days required by the larvae for residence 

 in the host. The twelve beasts came under observation on various 

 days between the 4th May and the 15th June and on the latter date 

 30 larvae were discovered under the skin. Comparing the results 

 obtained with those of the previous year, the stay of the larvae in the 

 host was apparently shorter in 1913 than in 1912, though, as it was 

 impossible to determine the exact date on which the larvae took up 

 their position, the period of residence was uncertain. Enquiries made 

 amongst farmers elicited the opinion that extra feeding during the 

 winter hastens the maturation of the larvae, and if this is really the 

 case, extra food in winter will enable the larvae to be removed from 

 the cattle before they are turned out to graze, thus ensuring the 

 destruction of a high percentage of them. The animals under obser- 

 vation were infested by both Hypoderma hovis and H. lineata. The 

 larvae of H. lineata are smaller and brownish grey, whilst those of 

 H. hovis are larger and of a greenish brown. It would appear that 

 the larvae of //. lineata reach maturity earlier than those of H. hovis. 

 The relative percentages of H. hovis and H. lineata were 79 and 21 

 in 1912 and 76 and 24 in 1911. These proportions are apparently 

 dependent to some extent on the weather. Bad weather in May and 

 June affects H. lineata more than H. hovis and thus alters the per- 

 <!entage of the larvae found later in the year. With regard to pupation, 

 experiments were made in fiower-pots with 375 larvae. Neither cold 

 nor damp seems to have any effect on pupation, w^hich seems to be 

 very little more than a hardening of the external integument. If the 

 temperature was high and the weather at the same time dry, pupation 

 was completed in 24 hours, but in unfavourable conditions might 

 occupy from two to four days. The process is more rapid with 

 H. lineata than with H. hovis. The duration of the pupal period was 

 found experimentally to be 23 to 38 days in the case of H. lineata 

 and 37 to 56 days in the case of H. hovis. The pupal stage oi the males 

 was shorter than that of the females. 



Sergent (E.), Lemaire (G.) & Senevet (G.). Insects transmetteur 

 et reservoir de virus du Clou de Biskra. Hypothese et experiences 

 pr61iminaires. [The insect carrier and the reservoir of the virus 

 of Biskra sore. Hypothesis and preliminary experiments.] — Bull. 

 Sac. Path. Exot., Paris, vii, no. 7, 8th July 1914, pp. L .'7-579. 



The connection between PJdebotomus and Biskra sore is argued 

 from the fact that most of the cases occur in those houses in which 

 Phlebotomus are most numerous. The species belonging to the group 

 of P. papatasii, Scop., apparently bite man by preference and almost 

 exclusively, but those belonging to the group of P. minutus, Bond., 

 normally feed upon reptiles. Both species exist at Biskra, and the 

 gecko, Tarentola mauritanica, L., is very common in all the houses. 

 It therefore appeared desirable to enquire as to how far P. minutus 



