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LuTZ (A.), DE SouzA Araujo (H. C.) & Da Fonseca (0.). Viajem 

 scientifica no Rio Parand e a Assuncion com Volta por Buenos 

 Aires, Montevideo e Rio Grande. [A scientific Journey on the 

 River Parana and to Assuncion and the Return Journey over 

 Buenos Aires. Montevideo and Rio Grande.]— Mem. Inst. Oswaldo 

 Cruz, Rio de Janeiro, x, no. 2, 1918, pp. 101-173, 108 photographic 

 figs. [With an English Summary.] [Received 1st December 

 1919.] 



A number of entomological notes made on this journey are 

 given. Blood-sucking insects observed while travelling on the rivers 

 included Tabanids, such as Lepidoselaga lepidota, Diachlorus flavitaenia 

 and D. binmculata ; these flies invade the boats even in broad daylight. 

 Esenbeckia spp. also follow the rivers, but are not much in evidence 

 in daylight. Chelotabanus aurora, a fluviatile species, is seen at 

 dusk. At some distance from the shore, mosquitos are not seen on 

 board in daytime, but at night some species, chiefly Taeniorhynchus 

 (Mansonia) and Anopheles {Cellia), are attracted by lights. 

 Simulium amazonicum is found on all the large rivers where there 

 are falls and is most annoying on the water ; on shore horses suffer 

 more than their riders. 



Anopheles (Cellia) argyrotarsis, the vector of malaria on the Upper 

 Parana, and a few examples of A. [C.) albimanus, also from the river, 

 were the Anophelines met with. Stegomyia fasciata occurred at 

 Baurii and at Tres Lagoas, the first station on the Corumba railway, 

 along which its spread is assured. The most troublesome mosquitos 

 met with were Culex fatigans {quinquestriatus), C. confirmatus [scapu- 

 hris), C. albofasciatus, Janthinosoma arribalzagae and Taenior- 

 hynchus (Mansonia) HtiUans. C. fatigans occurred nearly everywhere. 

 C. confirmatus is very common on the Upper Parana. It is not 

 numerous on moving vessels, but when they come to the banlc it 

 invades them in company with J. arribalzagae. Its larvae are seldom 

 found. This and the frequent occurrence of rubbed specimens 

 appear to point to this species being long-lived. It is common in 

 Paraguay and Argentina where there are trees. C. albofasciatus 

 resembles the preceding species in many ways. It bites in sunlight. 

 When attracted by artificial light it enters houses and boats in large 

 numbers. Until recently it was only known from Argentina ; on 

 this journey it was seen below Corrientes and — on the return journey — 

 in the harbour of Rio Grande. The eggs obtained from captured 

 females were laid separately and resembled those of Stegomyia. They 

 sink easily, but develop even under water, though less quickly. The 

 larvae take at least 5 days to develop. The larval stage lasts about 

 2 weeks and the nymphal period, a little less than 3 days. Janthino- 

 soma arribalzagae was not uncommon on the Lower Parana and in 

 Paraguay, while on the upper river and its affluents it attacked all 

 those who went ashore and invaded the boats. It is exclusively found 

 on the banks of rivers in which it must breed, as there is frequently 

 no other water. No larvae were obtained. The eggs are single, 

 black and similar in shape to those of Stegomyia. In spite of repeated 

 experiments no larvae were hatched, this probably indicating peculiar 

 biological conditions. Some specimens were quite typical, but others 

 aeemed transitional to J. albigena, of which typical specimens were 



