CULEX TEEKITANS 297 



the water — some of them six or eight inches above the water-level. It was also 

 noticed that the longitudinal axis of the cluster was always vertical and there 

 could be no doubt that the eggs were deposited in that situation. These egg- 

 boats were easily detached and when placed in water floated in the ordinary 

 manner of the eggs of Culex pipiens and Culex resiuans and the eggs hatched 

 within a day. The larvae from these eggs proved to be those of Culex territans, 

 which was also the most abundant form in the barrel in question. It may be 

 added that this rain-barrel stood in a large and well-shaded picnic grove and 

 nearby were several small ponds fed by springs where the larvae of Culex 

 territans, and of that species only, were abundant. Upon a previous occasion 

 four egg-boats of Culex territans were found at the margin of one of these little 

 ponds. They were under a projecting tussock, attached to its base just above the 

 surface of the water. Doubtless the eggs find their way to the surface of the 

 water by some mechanical means and most likely are washed down by a heavy 

 dew or a rain. Probably they do not hatch until they reach the water. 



" Upon August 16, 1904, it was my good fortune to come upon a mosquito of 

 this species in the act of ovipositing. In the above mentioned grove was a dis- 

 carded dish-pan partly filled with rain-water and upon its steep side the mosquito 

 was depositing its egg-cluster. About half the eggs were already laid. The 

 mosquito sat face upward, the tips of her hind legs just touching the edge of the 

 water. Her legs were placed well apart in the ordinary resting attitude, her 

 abdomen turned abruptly downward. A very slight backward and forward 

 motion of the abdomen could be discerned as the eggs were extruded in rather 

 quick and regular succession. The last half of the cluster was laid in about 

 eighteen minutes — ^from 10.45 to 11.03 in the forenoon. The manner in which 

 the eggs are extruded and placed against the preceding ones is remarkable. 



" Although the abdomen is bent almost straight downward, the mouth of the 

 ovipositor is turned dorsally and upward so that the egg, which appears with 

 the tapering end foremost, is pushed upward along the dorsal side of the abdo- 

 men until nearly the entire egg is exposed. A slight backward motion of the 

 abdomen then pushes the egg against the cluster, the basal part of the egg being 

 first brought in contact. When oviposition was completed the mosquito walked 

 slowly up the side of the pan and was then captured. 



"The completed egg-cluster contained 133 eggs laid in eight very regular 

 rows, with the slightly curved eggs all turned in the same direction. Only at one 

 end of the cluster, that towards which the eggs are curved, and its beginning, I 

 judge, the regularity of the arrangement is broken. The number of eggs in each 

 row was as follows : 11, 16, 18, 19, 19, 19, 18, 13. The egg is cylindrical, about 

 four times as long as broad. The lower end is spherically rounded ; the upper 

 third tapers very gradually, is slightly curved, and ends in a blunt point. The 

 color, by direct light, is brownish gray, darkening at the tip. The surface of the 

 egg appears smooth, but under a high power is seen to be very finely and rather 

 closely granulate. Along the sides are traces of the secretion by which the eggs 

 were fastened together. The eggs adhere together quite firmly and it is only by 

 some little force that one of them can be detached. As a result of the slight 

 taper and curvature of the eggs towards the top the cluster is slightly convex at 

 the bottom. Before hatching the eyes of the larva show through as two dark red 

 spots about one-fourth above the base of the egg, and the segments of the larva 

 may be also faintly discerned. The eggs when first laid are pure white, shining, 

 and darken very slowly. When examined three-fourths of an hour later (11.50) 

 they were still white and an hour after this (12.50) they were just tinged with 

 blue gray. Two hours later (3.50) they were of a gray such as that of the freshly 

 broken surface of cast iron, and at 4.30 they were a dark iron-gray and had not 

 yet attained their full coloring. 



