1917] Insects in Burmese Amber 327 



tibia and tarsus have short hairs, and short spines at intervals. The 

 following measurements are in microns: Length of wing about 2000; 

 length of cell in fork of media, 800 ; length of radial sector beyond origin 

 of upper branch, 624; length of antenna, 1200; third antennal joint, 

 160, sixteenth 80; length of abdomen as far as preserved (see Figure), 

 1120; hind tibia, 1120; joints of hind tarsus, (1) 608, (2) 224, (3) 160, 

 (4) 88, (5) 96. The thorax is shriveled and distorted in the type. 



Burmese amber, from R. C. J. Swinhoe. In outer slab 

 cut from same lump as slab containing the type of Acmaeodera 

 biirmitina etc., about 10 mm. from the angular corner. 



This remarkable fly is evidently allied to Macrocera, a genus 

 which occurs in the modern fauna, and also in diverse forms 

 in Baltic amber. The venation is very similar to that of 

 Palaeoplatyura, which Johannsen regards as the most primitive 

 in the Mycetophilidae, but there is absolutely no radio-medial 

 cross vein, and the strongly setose thorax also disagrees with 

 that genus. 



Trichoptera. 



Plecophlebus new genus. (Odontoceridae ?) 

 Small species with anterior wings moderately broad, obtuse apically, 

 not densely hairy. vSubcosta rather short, not connected with radius; 

 radius deflected downward toward the end, thence curving and even- 

 tually meeting the sector at right angles, but before that emitting three 

 branches to costa ; sector enclosing a long discoidal cell ; upper branch 

 of sector emitting at end two branches directed obliquely upward to 

 apicocostal margin, and also with a cross-vein to second branch, thus 

 enclosing an elongate cell, the base of which rests on the discoidal; 

 third branch of sector (R5) simple, arising from lower apical comer of 

 discoidal cell ; no chitinous dark dot in third apical cell ; anterior branch 

 of media not forked; median cell present, elongated; M3 and M4 

 separating beyond end of median cell; structure of cubital and anal 

 veins not ascertainable. 



Plecophlebus nebulosus sp. n. 



Anterior wing about 6 mm. long, hyaline, with suffused brown 

 spots as shown in Figure. 



Burmese amber, from R. C. J. Swinhoe. I had determined 

 this as a new genus, and on submitting a sketch to Dr. N. Banks, 

 he kindly informed me that no genus with such characters 

 was known to him. Dr. Banks pointed out certain resem- 

 blances in the upper part of the, wing to the Odontoceridae, 

 and it is to be remarked that the Odontocerid genera Electro- 

 cerum and Marilia, which occur in Baltic amber, have the 



