36 MISCELLANEOUS PAPERS. 



irregular dots near the i>osterior margin. The nietathoracic segment is Uke the last, 

 except that the dark color on the anterior margin is wider and the posterior, instead 

 of being dotted, is uniformly brown. The abdominal segments are each similar to 

 the nietathoracic, but the dark markings in the region of the lateral grooves are more 

 or less abbreviated. Last abdominal segment with two pairs of dark markings; the 

 ventral pair extend the whole length of the segment and are connected just behind 

 the anal prominence by a cross-band; the dorsal pair are oblong, somewhat irregular 

 in outline, and extend from the anterior margin to beyond the middle of the length. 

 At the anterior ventral border of each of the first seven abdominal segments is a 

 transverse series of prolegs, three on either side of the midventral line. These pro- 

 legs are located within the dark transverse bands, but are lighter in color than these 

 and prominent enough to be seen easily. Above the prolegs on either side of the 

 middorsal line is a small swelling which appears as a rudimentary proleg; before the 

 two is a distinct transverse light spot still within the dark area. 



The head of the larva is very small for so large an insect an'd the mouth parts are 

 minute. The mandibles consist of two strongly chitinized jjieces, and work by being 

 pushed endwise backward and forward. When drawn in, the anterior ends point 

 directly forward, but when protruded, these same ends jjoint downward and l)ack- 

 ward, thus forming a pair of hooks by means of which the prey is held. The larva 

 is able to protrude its mandibles very quickly and to use them very effectively on 

 soft-bodied invertel)rates on which it is known to feed. 



Pupa (fig. 10, b) about \\ inches in length. Color Ijrovvnish yellow. Antennal and 

 other tubercles of the head darker than the surrounding parts. Prothoracic spiracle 





y. 



Fig. 10. — Tahanus atratus: B, pupa; a. terminal abdominal teeth of same. Enlarged 



(original). 



slightly elevated, clear l)rown in color, reniform and oblique, rima gradually curved 

 to near the dorsal end, where a distinct hook is formed by a sharp bend. Abdominal 

 spiracles nearly round; rima of the first short and gradually curved and with a slight 

 hook at the dorsal end. Terminal teeth (fig. 10, a) arranged in pairs, a ventral 

 pair and a pair on each side formed by a dorsal and a lateral tooth. The distances 

 between these teeth is varial)le; the two dorsal are nearest together, then follows the 

 distance between a dorsal and a lateral, the distance between the two ventral, while 

 the distance between a ventral and a lateral on each side is greatest of any. 



THE MARSH EARFLY. 



( t'lirysops mareiis Walker. ) 



The raarsli earfly is a common species in the marshes near the Lake 

 Laboratory, at Sandusk}', Ohio. The adults appear each year during 

 the hitter part of June and are abundant by the 10th of July, They 

 continue to be common all through the latter month and August, and a 

 few are to be found in September. Eggs were first observed during 

 the first days of July and were present in varying numbers during the 

 following two months. 



During the time the female is ovipositing she is not easil}' disturbed; 



