214 



In general A. maculipennis prefers clear water for breeding, and 

 requires sunny situations. The presence of the larvae of this species 

 not only depends on the water and on the vegetation, but also on the 

 presence of cattle, and this last fact may explain the changing location 

 of the breeding-places in the course of the summer. A map of the 

 distribution of A. maculipennis around Hamburg is given. 



The author does not consider it proved that A. hifurcatus comes 

 indoors less readily than A. maculipennis. All its breeding-places 

 were in either haK or full shadow. As this species hibernates in the 

 larval stage, it is obviously necessary that the water should not become 

 entirely frozen, and this involves the necessity for a certain degree of 

 inflow from the bottom. 



A. plumheus [nigripes) occurs near woods where there are tree-holes 

 that serve its larvae as breeding-places. It does not appear to come 

 indoors, and is of Mttle importance as regards malaria. 



Most of the locahties in which malaria was endemic in the eighties 

 and nineties of the last century may be regarded as still inconspicuously 

 malarious, and careful examination of the children in them would 

 reveal a number of carriers. The reasons why the disease has decreased 

 in Germany are the cheapening and availability of quinine, the changes 

 leading to a gradual eHmination of mosquito breeding-places, and 

 changes in the habits of the population, which have made transmission 

 more difficult. The author is convinced that a sinking of the level 

 of subsoil water must lead to a reduction in the number of mosquitos. 

 The peasants now live in modern houses where mosquitos are not able 

 to enter with the same ease as previously, where the bed-rooms are 

 more distinctly separated, and where the indoor temperature is not 

 so high, so that the parasites can only develop during a limited part 

 of the year. 



To reduce the malarial incidence still further, breeding-places 

 must be eliminated ; in marshlands where this is not possible, 

 screening must be resorted to. ^^ 



Martini (E.). Ueber mecklenburgische Culieinen. [Mecldenburg 



Cuhcines.] — Sitzungsber. u. Abh. naturf. Ges. zu Rostock, N.8.^ 

 vii, 1920, pp. 203-208, 1 plate. 



The two new species, Aedes (Ochlerotatus) rostochiensis and A. (0.) 

 semicantans, previously recorded from Mecklenburg [R.A.E., B, viii, 

 171] are described and figured. The larva of the former was found 

 in ditches or water-holes at the edge of woods ; that of the latter 

 in turf -cuttings at the bottom of which there was peat-moss. 



The author has observed the following mosquitos in Mecklenburg : 

 Anopheles maculipennis, A. plumbeus {nigripes), A. bifurcatus, Aedes 

 nemorosus, A. sylvae, A. terriei, A. rostochiensis, A. salinus, A. diversus^ 

 A. ornatus, A. cantans, A. annulipes, A. abfitchi, A. semicantans, 

 A. vexans, A. dorsalis, A. cinereus, Theobaldia annulata, T. morsitans, 

 Culex pipiens, and Taeniorhynchus richiardii. 



Among the German mosquitos not yet recorded from Mecklenburg 

 are Aedes quartus and Culex territans, but the nature of the country- 

 makes it probable that they do occur there. 



