Marshall. — On Neio Zealand Diplera. 223 



sheds, in damp, dark places in bush, also in caves, and in 

 similar localities. 



KEY TO THE FAMILIES OP NEMOCERA. 



A. Thorax without any transverse suture. 



a. Tibite not spurred. 



* Wings haired. 



Longitudinal veins few. Cecidomyidce, 1. 

 Longitudinal veins numerous. Psychodidce, 10. 

 ** Wings naked. 

 § No ocelli. 



1. Legs liairy ; antennae with not more than 12 joints. 

 Costal vein continued round the margin of the 



wing. Culicidc^, 7. 

 Costal vein terminating near the apex of tlie wing. 

 Chironoviidce, 8. 

 '2. Legs rather short ; antenna short. 



Costal vein continued roiind the posterior border. 

 Orphnephilidcs, 9. 

 3. Legs short; antennae with not less than 12 joints. 

 Siniulidce, 4. 

 §§ Ocelli present. 



No discoidal cell. BibionidcB, 5. 

 A discoidal cell. Bhyphidcn, 1-3, 



b. Tibiae spurred. 



§ No ocelli. / 



All tibiae spurred. Dixidce, 12. ^° 



§§ Ocelli present. 



Anterior tibite spurred. Blepharoceridcs, 6. 

 Ail tibiae spurred. Mi/cetophilidcE, 3. 

 With or without spurs. Sciaridce, 2. 



B. Thorax with a V-shaped transverse suture. Tipiilidce, 11. 



TEEMINOLOGY. 



As regards the technical terms employed, I feel I cannot 

 do better than transcribe the following pages from Skuse's 

 paper. The terms described are those made use of by Osten- 

 Sacken and Loew in their monographs of the Diptera of North 

 America. 



1. The Head. 



The back of the head opposite the thorax is the occiput, 

 and is prominently perceptible in both Diptera and Hymenop- 

 tera carrying their heads free. That portion of it lying over 

 the attachment of the head is the nape (cervix). The front 

 forehead or brow (frons) is that part of the head stretching 

 from the antennae as far as the occiput, and is limited laterally 

 by the compound eyes. The crown (vertex) is that part of the 

 head on which there are usually the simple eyes (ocelli), 

 generally three in number. The limit between the occiput 

 and front is styled the vertical margin (margo verticalis). 

 Most of those Diptera undergoing their metamorphosis within 



