124 NEW YORK STATE MUSEUM 



larvae; but it does not appear to open to the surface. (Miall and 

 Hammond, 1900.) T any pus larvae are said to make tubes 

 like those of C li i r o n o m u s , but in captivity they seldom seem 

 to do so. 



Pupa. Greatly resembles that of C u 1 e x , but differs in the 

 form of the breathing trumpet, the form of the caudal fin, and in 

 lacking the stellate hairs on the posterior margin of the thorax. 

 It often remains below the surface but can come up to breathe. 

 When alarmed it sinks and often holds on to objects at the bottom 

 of the water by means of its tail. The pupa is further provided 

 with suckers on the abdomen, which enables it to hold on to solid 

 objects. Meinert (1886) says that the suckers are circular de- 

 pressions outside the dorsal shields of the abdomen. The pupa of 

 Tan y pus varius shows them most distinctly. Here they 

 are borne in pairs by four abdominal segments (3-6). When 

 the pupa has attached itself by a single sucker, it can turn about 

 without losing its hold. The form of the pupa is shown on pl.l9, 

 fig.8. The thorax is large and bulky, the abdomen slender and 

 curved under the thorax. The breathing trumpets vary in the 

 different species (figs. 2, 3, 7, 13, and IS) ; in some species they 

 are long, slender, cylindrical, and tube-like; in others spindle- 

 shaped or funnel-shaped; and in one an elongate ellipsoid with 

 a small aperture. The surface may be smooth, spinose, or reticu- 

 late. On the dorsum of the thorax back of the trumpets there 

 is, in some species at least, a row of short spines (pl.l9, fig.8). 

 The wings, legs, antennae and eyes of the adult are distinctly 

 visible in the more mature pupae. There are seven abdominal 

 segments besides the anal to which the caudal fin is attached. 

 There are no distinct spinose markings in the species which I 

 have examined. The caudal fin varies with the different species; 

 in some it is composed of two pointed projections, in others these 

 are more lobe-like, while in an extreme form it is in the form of 

 a rounded paddle rpl.l9, figs. 4, 6, 15, 19, and pl.20, figs. 4 and 8). 



The imago. Body elongate and pubescent. Eyes separate in 

 both sexes. Palpi four-jointed, curved, first joint shorter than 

 the second, second shorter than the third, fourth nearly as long 

 as the second and third. Antennae in both sexes fifteen-jointed, 

 filiform, seated in a notch in the eyes; plumose in the male, joints 

 two to thirteen very small, fourteenth long, fifteenth short and 



