30 PROCEEDINGS OF THE ACADEMY OF [1896. 



low mark ou the front, the frontal mark, but this is not very com- 

 mon. 



Finally, just below each antenna may be a small subtriangular 

 mark, which I have called the dog-ear mark, because of its resem- 

 blance to the ear of a hound, first observed In the $ form described 

 as canina. 



In the males the face is frequently all yellow or white up to the level 

 of the antennce; and then good characters are found in the degree of its 

 further upward extension, and in the form of its upper limit. 



The face markings are nearly always conspicuously different in 

 the sexes, but not so in alhovittata and the albipermis group, nor in 

 luteola, nor the texana group. 



The pale markings of the thorax are confined to different degrees 

 of yellow on the prothorax, often affording good characters, and 

 occasional very characteristic yellow patches on the pleura, except 

 in mexicanorum, which has a yellow postscutellum, and luteiceps, 

 which has a little yellow on mesothorax and scutellum. Two spe- 

 cies, punctoslgnata and cephalotes, have the thorax yellow with black 

 markings ; marcialis has it yellow with green markings, the meso- 

 thorax being green with yellow lateral margins. 



The wings may be simply hyaline or milky-hyaline, or slightly 

 smoky; never really dark and never spotted or banded. The 

 nervures and stigma may be dark brown, light brown, yellowish or 

 colorless ; the stigma is usually hyaline centrally. In the texana 

 group the stigma is hardly developed. 



Very good characters are 'found in the venation. The marginal 

 cell differs greatly in size and length, but I never saw one so 

 long as to suggest the condition of Calliopsis. It may be obliquely 

 or squarely truncate. It may have the portion below the stigma 

 (substigmatal) longer than that beyond ( poststigmataV), but usually 

 they are about equal or the latter is longer. There are but two sub- 

 marginal cells ; and the shape of the second, whether triangular or 

 how much narrowed to the marginal, should in each case be noted. 

 The so-called second submarginal is morphologically the third, the 

 true second of genera with three submarginals being absent. On 

 one side of the type 9 of obscui-ata, the true second submarginal 

 actually appears, small, triangular and petiolate, much as in the 

 Larrid genus Plenoculus. 



The third discoidal cell may be very weak or even entirely want- 

 ing, according to the development of the second recurrent nervure. 



