WERNER MARCHAND 47 



oviposition, as with other species of Chrysops and Tahanus; Hine has 

 seldom observed females ovipositing at other hours of the day. 



The eggs when first laid are clear white but gradually get darker 

 until they become permanently dark brown or black. It took eggs 

 of Chrysops callidus 5 or 6 days to hatch, and it required about a day 

 longer in the case where eggs were kept in the shade the whole time 

 than in cases where the eggs were in the sun during the day.^ 



The writer has made some additional observations on Chrysops 

 callidus, which are published elsewhere. 



Chrysops celer Osten Sacken. — A species recorded from Maine, 

 Massachusetts, Pennsylvania, New Jersey, Ohio, and North Caro- 

 lina. This species is common in Ohio during the latter half of May. 

 The eggs have been observed commonly by Hine along the margin 

 of ponds and artificial lakes, clinging to various kinds of foliage over- 

 hanging the water. The female has been observed ovipositing on 

 different occasions, and is the only species of the genus placing its 

 eggs in masses composed of layers one above the other as in Tahanus. 



Chrysops dispar Fabricius. — This species is widely distributed in 

 India, Ceylon, Malay, and adjacent parts. We possess some infor- 

 mation on its early stages through the work of Patton and Cragg in 

 Madras (1913). 



^In the summer of 1916, I collected the eggs of Chrysops callidus 0. S., in 

 Princeton, N. J., from which the young larvae were obtained. These are half 

 transparent, whitish, and their structure is analogous to that of most tabanid 

 larvae, differing, however, from the young larvas of Tahanus, as far as known to 

 me, by having the main tracheal trunks not inflated, but of about equal diame- 

 ter all along their course. This character ("not provided with air sacs") is, 

 however, given by Patton and Cragg for all "small tabanids" observed in Mad- 

 ras, including species of Chrysops, Tahanus, and Hcematopota. It causes the larva 

 of Chrysops callidus to sink to the bottom instead of floating to the surface. The 

 larvae of this species molt soon after hatching, and can live under water for a 

 considerable time, but as all the larvae died in young stages, I am unable to 

 say what their further habits are, and whether they spend most of their life in 

 the water or later on invade the mud of the shore. At a pond where large 

 numbers of Chrysops had oviposited the previous summer, in spring no larvae 

 could be detected in the mud of the margin, while other tabanid larva3 were 

 numerous. 



For further details see Marchand, /. N. Y. Entomol. Soc, 1917, xxv, 149. 



