359] LARVAE OF THE TENTHRED1N01DEA—YUASA 41 



not permit a characterization of the genera. The following key will serve to 

 separate the species: 



1 (8) Larvapods present on all abdominal segments, those on the first and ninth segment 

 sometimes rudimentary; thoracic legs normal in form; body tuberculate, tubercles 

 setiferous, concolorous with the head; head creamy or brownish or blackish; abdom- 

 inal segments typically with four annulets, first annulet smooth, non-tuberculate, 

 crescentic, and confined to the dorsal aspect, three following annulets convex, with 

 transverse row of setiferous tubercles; not on staminate flowers of conifers 2. 



2(7) Head dark-colored, brownish or blackish; tenth abdominal tergum always and 

 prothoracic and ninth abdominal terga usually with dark-colored patches; tenth 

 tergum brownish or blackish; subanal lobe with a pair of wart-like brown tubercles 

 which bear blackish brown setae on the dorsal and lateral aspects, less densely on 

 the ventral aspect; dorsal tubercles arranged typically as follows: the second and 

 third annulets with four to five, the fourth annulet with two or three; the subspiracu- 

 Iar and surpedal lobes, each with a tubercle; the dorsal tubercles of the second annu- 

 let with one to three setae 3. 



3(6) Tubercles of typical abdominal segment arranged as follows: second and third 

 annulets with four tubercles above the spiracular line, each tubercle bearing one 

 seta, the fourth annulet with two tubercles, one on the spiracular line with two setae, 

 the other, dorsad of the line, with one seta; on hickory and pecan 4. 



4(5) Prothoracic tergum with a large dark brown, median patch whose lateral margins 

 converge toward the cephalic margin, which is one-half as long as the caudal margin; 

 the ninth abdominal tergum with a large dark brownish patch on each side of the 

 meson, the patches converging toward the caudal margin so that the caudal halves 

 are nearly confluent on the meson with a pair of brownish tubercles btween the 

 cephalic halves; tenth abdominal tergum almost completely dark brown in color; 

 the first annulet of typical segment with the dorsal pair of tubercles quadrate, one- 

 half as long as the annulet; abdomen with a brownish, cloudy, longitudinal dorso- 

 lateral line involving the dorsal pair of tubercles and extending usually from the 



second abdominal segment to the seventh; on hickory and pecan; Y-226, G 



Megaxayela major Cresson. 



5(4) Prothoracic tergum without a large dark brownish median patch, but with a pair of 

 small blackish patches distinctly separated on the meson of the first and second 

 annulets, the cephalic pair larger, triangular, and their apices directed laterad, the 

 caudal pair subquadrate, further apart than the cephalic pair; the ninth abdominal 

 tergum without a pair of large dark brownish patches but with two pairs of small 

 blackish patches, distinctly separated on the meson, the cephalic pair smaller and 

 slightly further apart than the caudal pair; tenth tergum blackish, with its cephalic 

 constricted portion pale or creamy; first annulet of typical abdominal segment with 

 the dorsal pair of tubercles subcircular, one-third as long as the annulet; abdomen 



without a brownish, cloudy longitudinal dorso-mesal lines; on pecan; Y-227 



Megaxyela sp. 1. 



6(3) Tubercles of a typical abdominal segment arranged as follows: second and third 

 annulets with four to five tubercles above the spiracular line, each tubercle bearing 

 two setae; the fourth annulet with three tubercles, one on the spiracular line and the 

 other two dorsad of it, each tubercle with two setae; on hickory and butternut; 

 Y-228 ; Odontophyes aviingrata Dyar. 



7(2) Head light in color, creamy white or pale brown; the prothoracic and the ninth 

 and tenth abdominal terga without dark-colored patches; tenth tergum light brown; 

 subanal lobe with a pair of wart-like creamy tubercles which bear long light brown 



