103 



wHch is a common mosquito in Manila and the vicinity and also 

 has a wide general distribution. In spite of the high death rate 

 from malaria, no efforts are being made to suppress Anophelines, 

 and favourable conditions for their development seem to be increasing 

 in Manila. More deaths occur in the Islands from this disease than 

 from tuberculosis or cholera, as shown in a comparative table. 



Leiva (L.). Mosquitoes around Manila and Vicinity : a Health Problem. 



• — Philippine Jl. Science, Manila, xiii, no. 6, sec. B, November 

 1918, p. 339. [Received 10th April 1919.] 



The attention of the Manila Medical Society has been called to the 

 presence of Culicine and Anopheline mosquitos in Manila and its 

 vicinity. Owing to the shortened route between the yellow fever 

 zone and Manila due to the opening of the Panama Canal, cases of 

 this disease may pass the quarantine station in the incubation period, 

 and the position will be a serious one should there be a Philippine 

 species of mosquito able to transmit yellow fever. Stegomyia fasciata 

 persistans. Banks, has not yet been proved to be a carrier of the disease, 

 but both this and other species of Stegomyia are indigenous to the 

 Philippine Islamds. 



Edwards (F. W.). The Larva and Pupa of Taeniorhynchus richiardii. 

 Fie. (Diptera, Culicidae). — Entomologist's Mthly. Mag., London, 

 Iv, no. 659, April 1919, pp. 83-88. 



The hitherto undescribed early stages of this European mosquito 

 have the same remarkable structure and habits as the North American 

 T. perturbans, ^Vlk., both of them living among the roots of water- 

 grasses, from which they obtain their supply of air by the aid of a highly 

 modified spiracular apparatus. During June and July, T. richiardii 

 abounds in the winged state round a pond at Letchworth (Herts.), 

 both males and females, the former being much more numerous, 

 hovering among bulrushes and grasses round the water's edge. In 

 June 1918, about half a dozen full-grown larvae were obtained by 

 pulling up some of the water-grass {Glyceria jluitans) and shaking 

 out the roots, and in the following November a few half-grown larvae 

 were similarly found, suggesting that probably this species, like 

 T. perturbans, hibernates in the larval state, and that there is only 

 one generation in the year. 



The breathing tube closely resembles that of Mansonioides africanus 

 [see this Review, Ser. B, vi, p. 38]. The larva of T. richiardii has 

 another remarkable adaptation, which has not been previously observed, 

 consisting of a pair of large air sacs in the thorax, formed by dilatations 

 of the small f orwardly-proj ecting tracheal branches in the first 

 abdominal segment. These, which do not occur in any other British 

 or figured American species, resemble the thoracic air sacs of Chaobcrus 

 {Corethra) and Mochlonyx, and perhaps function as oxygen storehouses 

 necessary for hibernation. The pupa is also adapted to a subaqueous 

 existence. 



