1920] Richmond, Studies on the Biology of the Aquatic Hydro philidce 61 



Fcll-gkovx Larva. — Length, 7-10 mm. ; width, 1.25-1.8 mm. Orange-colored 

 and. when it is not too dirty, has a peppery appearance due to the dark coloration of 

 the integument at the base of the spines which cover the body. A striking transverse 

 row of dark spots is noted in some larva? on the tops of the abdominal folds. Head, 

 dorsally, is 0.77 mm. long and 0.64-0.9 mm. wide. Spines of labro-clypeus mostly 

 lost and teeth present a scalloped appearance. Anterior inner teeth of mandibles 

 without serration. 



Pupa. — Length, 7 mm.; width at its thorax, 3.2 mm. Whitish. Head smooth 

 and bears two supraorbital styli on each side. Pronotum smooth, its anterior 

 margin somewhat trilobed and its posterior margin straight, slightly indented just 

 in front of the base of the elytra. The styli are arranged as follows: ten on the 

 rounded lateral and anterior margins, two of which are on the middle lobe; eight on 

 the posterior margin, counting the two corner ones; two on the middle lobe just 

 posterior and slightly lateral of the two anterior styli; and a transverse row of four 

 in the middle, the outer two a little anterior to the inner two. Mesonotum and meta- 

 notum with a transverse row of two styli. Inner spur of metatibia fairly prominent. 

 Tarsi not ending in a spine but blunt and tibiae not spinous on the outer side. Meta- 

 thoracic pterothecae visible from above. First abdominal tergite with a transverse 

 row of four styli; second to seventh abdominal tergites, inclusive, with a transverse 

 row of six styli, the outer one on each side arising from tubercles; second to seventh 

 pleurites each with a stylus; eighth tergite semicircular, the rounded posterior margin 

 bearing two styli; ninth segment with a pair of cerci, a little longer than the eighth 

 and ninth segments together (0.72 mm.), extending caudally and very slightly diverg- 

 ing; ninth sternite with prominent acute externo-caudal angles, a pair of appendages 

 arise from between the eighth and ninth, sternites and extend caudad on either side 

 of the median line as far as the base of the cerci and closely appressed. Spiracles 

 fairh- prominent and slightly raised. 



Cymbiodyta blanchardi Horn 



The different stages of this species seem to be practically identical 

 with C.fimbriata except that they are smaller in size. The larva possesses 

 a pair of small, very indistinct, oval patches on the second to seventh 

 abdominal tergites, which were not present on the larvae of C. fimbriata. 



Helochares Mulsant 



The only eastern species, H. rnaculicollis, has not been recorded 

 from our fauna and is not to be expected. It is a more southern species 

 and reaches northward along the Mississippi River and its tributaries 

 only as far as Ohio, Illinois, and Missouri. According to Blatchley, 

 1910, it occurs very rarely in Indiana (Lawrence and Dubois Counties). 



