62 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 52 



deep black head, and comparatively short tube ; they are easily over- 

 looked, as they go down at the least disturbance and remain at the 

 bottom for a long time, burrowing in the mud. 



URANOT^NIA LOWII Theobald 



This species, which is still smaller than the foregoing, was bred 

 from similar black-headed larva? in a small semi-stagnant stream near 

 Las Cascadas. 



URANOT^NIA TYPHLOSOMATA Dyar and Knab 



Bred by ]\Ir. A. H. Jennings from a still pool in the small stream 

 supplying the water-tanks of the Pacific Alail Steamship Company on 

 Taboga Island. 



Genus PSOROPHORA Desvoidy 

 PSOROPHORA IRACUNDA Dyar and Knab 



The large predaceous larvae of this species were taken in numbers 

 near Las Cascadas in a newly flooded meadow covered with bushes 

 and tall grass. They were preying upon the larvze of Culcx lactator 

 and Janthinosoina posticata, which were very abundant in these tem- 

 porary pools. The larvffi are very voracious, biting and even eating 

 each other if confined together. Apparently their development is 

 quick. All the larvae taken pupated within a day, and adults issued 

 from all of them within the next two days. This species was taken 

 in Alay. 



PSOROPHORA SiEVA Dyar and Knab 



The larvK of this species occurred sparingly at the same time and 

 together with those of the foregoing species, but a month later it 

 was the greatly predominating species in the same locality. It is a 

 similar but longer and more slender larva, with longer tube than that 

 of iracunda. 



Genus T^NIORHYNCHUS Arribalzaga 

 T^NIORHYNCHUS COTICULA Dyar and Knab 



A single specimen, caught, as it came to bite, in the black swamp 

 near Lion Hill. 



The larvcC of this and the following species may be expected to 

 have a similar specialized life-mode to our Tceuiorhynchns pcrturbaiis, 

 which baffled entomologists for several years, before Prof. J. B. 

 Smith lately discovered that it lives several inches down in the mud 

 at the bottom of certain ponds, attached to the roots of plants. 



