SYRPHID^E. 



399 



Fig. 318. 



Fig. 3J9. 



flowers in the spring, and are common throughout the spring. 

 They scoop up the pollen of the flowers with their maxillae. 

 We have received from Mr. E. T. Cox the 

 puparium (Fig. 318) of a species which in- 

 habits the salt vats of the Equality Salt 

 Works of Gallatin County, 111. The pupa- 

 rium of a species of Helopliilus closely re- 

 sembling that figured by Westwood (Class. Insects, Fig. 131, 

 8), has been found living in the salt water canal of the 



Naumkeag Factory leading 

 into Salem Harbor, and is in 

 the Museum of the Peabody 

 Academy. 



Closely allied to Eristalis is 

 the genus Merodon, of which 

 M. bardus Say (Fig. 319 ; a, 

 puparium, natural size) is fre- 

 quently met Avith. Its thorax, 

 the first abdominal ring and the side of the second are cov- 

 ered with short yellow hairs ; it is .70 of an inch in length. 

 The puparium is of the same length, and 

 is cylindrical, ending suddenly in a re- 

 spiratory filament a little longer than the 

 body ; it is quite stout, contracting be- 

 yond its middle into a slender filament. 

 On each abdominal ring is a pair of small, 

 low, flattened tubercles crowned by a 

 number of radiating spiiiules. Its larva 

 is undoubtedly aquatic, like that of Eris- 

 talis. Mr. Sanborn has also reared from the pupa state M. 

 Narcissi, which probably lives in the soil about 

 decaying bulbs, as the puparium has no respira- 

 tory tube, but instead a very short sessile trun- 

 cated projection, scarcely as long aa it is thick, 

 with a pair of stigmata in the end ; the body is 

 cylindrical and rounded alike at each end, with a slight con- 



ries perfectly vivified; it is a true arterial blood. These capillaries arc not in 

 communication with the venous capillaries; the blood is taken up by the tissues, 

 it nourishes them and flows into the venous lacunae, and the lacunar currents 

 carry it to the dorsal vessel." Annales des Sciences Naturelles, 1868. 



Fig. 321. 



