RETURNING SWARMS IN AFRICA. 
79"" 
in the middle of the summer ; and return iu the winter, when they are of 
a maroon color, with the extremities yellow. It is evident that the win- 
ter hrood is not the same as the summer brood going south, nor do we 
presume the language used was intended to convey this idea. It appears 
from the statement of M. Girard that those hatched in Algiers, in 1866> 
migrated westward and southwest in January, hut this is spoken of as 
unusual. 
There is some evidence, though not decisive, that in Central Africa 
the resulting swarms return northward, as, for example, the swarm seen 
by Barth in July, 1854. 
M. Brue 175 mentions the fact of swarms which had moved southward 
in Senegal returning northward to the desert. The same disposition to 
return to the land of their nativity is exhibited by the offspring of those 
visiting Southern Africa. 
The locusts which plagued Pharaoh came from the east (Arabia) on an 
■east wind, and in attempting to return on a west wind were engulphed 
in the sea 176 . Richard Jobson, 177 notes a similar case. Mebuhr 178 says 
that swarms frequently cross the Bed Sea a second time and return to 
Egypt, the upp er part of which, adjoining the deserts of Lybia seems to 
be the cradle of these animals. Whether correct or not in reference to 
their " cradle," these reverse movements indicate clearly a disposition to 
return to the place of their nativity. 
From these facts, and others which might be mentioned, we feel justi- 
fied in assuming that it is a characteristic of this species, as of C. spretus, 
for the resulting broods to return to their normal habitat, especially 
where the direction of the invading movements is northward or south- 
ward. 
Shaw mentions expressly that the locusts return to the desert to de- 
posit their eggs. Speaking of his observations in Barbary, he says that 
towards the middle of April (1724) the locusts had so multiplied that, 
they formed clouds which darkened the sun. About the middle of May 
their ovaries were filled and they began to move backwards into the 
plains of Metidja and other adjoining regions in order to deposit their 
eggs. 
The same disposition to return to their native breeding grounds is 
shown by the A. paranense in its movements in Paraguay, as indicated 
by Bengger. 179 
c. Local flights. — In our former report this term was applied only to 
the movements of those locusts hatched in the temporary regions to and 
fro, from point to point, within that region. We adopted it chiefly to 
avoid circumlocution, and explained it to avoid confusion. The neglect 
to distinguish between such movements and real migrations has often led 
'"Ritter Hcuschreckenplage 19, Labat, Relat de l'Afrique, Occ. 2, 176. 
'"Ex. X. 
'"Visit to Gambora, Purchas, ii 1046. 
""Travels in Arabia, &c, Transl. ii 334, &c. 
*" Roise nacb Paraguay, p. 420. 
