186 Journal New York Entomological Society. ['^'o'- ^^■ 



my rearings the adults emerged on July 5, 1910, just seven weeks after 

 the eggs were laid. Unfortunately I had to stop my work at this 

 time and no further rearings have been made. 



Peltodytes edentulus Lee. 



The Egg. — Brownish in color, broadly oval, with roughened mark- 

 ings, a small knob on the anterior end. Length .466 mm. ; width .233 

 mm. The eggs are attached to the stems of aquatic plants, particu- 

 larly Nitclla and Chara (Fig. 33). 



It will be unnecessary to discuss the time of hatching, the different 

 instars, or the number of stadia as they are identical with those of 

 P. iiiiiticus Lee. It will be necessary only to point out the dift'erences 

 between the mature larvae of the two species. 



Mature Larvce. — Length, excluding the caudal setae, 6 mm. ; caudal 

 set?e, 4 mm. The dorsal and lateral spines are arranged similarly to 

 those in P. muticiis. Not the slightest difference can be observed. 

 The only point of distinction between the mature larvae of these two 

 closely related species is in the relative lengths of the short spines 

 present on the proximal segment of each dorsal spine. In P. niuticus 

 the lateral spine is longer than the thickness of the large spine while 

 in P. edeiifiiliis it is shorter (Figs. 28, 29.) Spirals are absent. 



Pupation.- — The time of pupation, the pupal chamber, the length of 

 the prepupal and pupal life are identical with that found in P. muticns. 

 So far as I can discover there are absolutely no differences between 

 the pupa; of the two species. 



Haliplus ruficollis DeG. 



This is the only species of the genus that I have succeeded in rear- 

 ing and of this species I have not yet been successful in securing 

 pupae. In 1910 many larvae died in trying to find suitable places in 

 which to pupate and I had to give up the work before I could secure 

 the necessary conditions for pupation in this species. 



As with the species of Peltodytes mating takes place in the water. 

 I found them freely copulating in spring-fed pools on May 9, 1910. 

 Several pairs in copula were placed in aquaria with abundance of 

 algae, particularly Nitella. On May 16 I found eggs placed within 

 the dead, hollow cells of Nitclla. The female cuts an opening with 

 her mandibles and then deposits several eggs within the cell through 

 this hole (Fig. 32). This is continued till quite a large number of 

 eggs are laid. 



