157 



Kellogg (V. L.) & Nakayama (S.)- Mallophaga of the Vizcacha. — 



Entom. News, Philadelphia, xxv, no. 5, May 1914, pp. 193-201, 1 pi. 



The authors describe two new Mallophaga taken by C. H. T. 

 Townsend on the Vizcacha {L'tgidium jjeruamcm, Meycn) in Peru, viz. : 

 Gyrojius alpinus, sp. nov., and Philandesia townsendi, gen. et sp. nov. 



Webb (J. L.). Arsenical Poisoning of Stock. — Agric. Jl. Union S. 

 Africa, Pretoria, vii, no. 5, May 1914, pp. 683-687. 



In the majority of cases loss of farm stock from arsenical poisoning 

 could be avoided were more attention paid to small details when 

 handhng arsenical mixtures. By the aid of the isometer the standard 

 strength of the dipping solution can always be maintained and need 

 never be made too strong. Even then scalding amongst cattle not 

 previously dipped may sometimes occur, but for the first six times, 

 three-quarter strength should be used, or if the tank be filled with 

 standard strength solution, dip once every 10 to 14 days during the 

 first 4 or 6 weeks. Dipping on wet or misty days should be avoided, 

 or the dip will not dry off, and, where possible, shade should be provided 

 for cattle which are being regularly dipped in full strength solutions. 

 The most frequent cause of stock poisoning is carelessness in 

 allowing tliem to have acce:)S to dipping solutions. Concrete sumps 

 should be fitted with heavy lids, suitable draining arrangements from 

 the sheds should be made, and when the tank is emptied a deep hole 

 should be dug in which the dip and refuse can be placed. A fence 

 should surround drying sheds and tanks. To prevent drinking during 

 the actual dipping, large and small animals should not be dipped 

 together, and beasts should not be allowed to follow each other too 

 closely. Cattle are occasionally poisoned by standard strength dips 

 applied at too frequent intervals. The paper closes with descriptions 

 of the symptoms, post mortem appearances, and treatment of 

 arsenical poisoning of stock. 



The Life-History of the Scab Parasite. — Agric. Jl. Union S. Africa, 

 Pretoria, vii, no. 5, May 1914, p. 725. 



Investigations regarding the hfe-history of the common sheep-scab 

 parasite {Psoroptes communis var. ovis) in South Africa have been 

 conducted at Pietermaritzburg and at Onderstepoort. Most of the 

 dipping fluids employed have failed to destroy the eggs, and it is 

 necessary to regulate the interval between two successive periods, 

 so that the second immersion is given before individuals hatched from 

 eggs that survived the first dipping begin themselves to oviposit. 

 According to observations at Pietermaritzburg, the second dipping 

 should be given on the eighth day after the first, and not later than 

 the ninth day according to Onderstepooii; results. The former probably 

 indicates the shortest possible period, and a dipping on the eighth 

 day will reach those acari which would lay their eggs as late as the 

 tenth day. The eggs all hatch within eight days, whether in the wool 

 or in direct contact with the skin. As the dipping fluid remains active 

 in the skin for one or two days, the period might be extended to nine 

 or ten days, but not later. 



