154 Maine Agricultural Experiment Station. 1918. 



Plica: a fold; a submarginal plica is a lateral fold in the elytron extend- 

 ing caudad from the umbo. 



Post-humeral depression : a depression behind the umbo which may or 

 may not be present. 



Tubercle, frontal: a chitinous plate immediately caudad of (i. e., supe- 

 rior to) the antenna. 



Umbo (plural umbones) : an elevation or swelling in the humeral aigle 

 of the elytron. 



Keys to the Maine Species of Altica. 

 Key to the Adults. 



(Including ignita 111. and "ignita" of Chittenden.) 



1. Elytra longitudinally plicate at the sides 2. 



1. Elytra not longitudinally plicate at the sides 3. 



2. Large blue species ; 5-6 mm. long bimarginata. 



2. Smaller species; 3-4 mm. long ignita Illiger. 



3. Thorax with a deep ante-basal groove which extends completely 



across the thorax 4. 



3. Thorax with a moderate ante-basal groove which does not extend 



completely across the thorax 8. 



4. Thorax distinctly wider at the base than at the apex chalybea. 



4. Thorax scarcely wider at base than at the apex 5. 



5. Brilliant cupreous or golden cupreous 6. 



5. Not so colored 7. 



6. Segment 3 of the antennae longer than segment 4; length 4 mm. 



- "ignita" of Chittenden. 



6. Segment 3 of antennae equal in length to segment 4; length 3 mm. 



rosae. 



7. Black; antennae three-fifth the length of the body comi. 



7. Green, blue, or violet; antennae one-half the length of body. .. .ulmi. 



8. Prothorax less than one-half wider than long carinata. 



8. Prothorax more than one-half wider than long torquata. 



Key to the Eggs. 



1 .Eggs deposited in l's or 2's 2. 



1. Eggs deposited in clusters of 3 or more 3. 



2. Eggs deposited on leaves (usually elm) ulmi. 



2. Eggs deposited on stems or ground at base torquata. 



3. Eggs orange, deposited in the tubes of leaf-rooling Lepidoptera 



bimarginata. 



3. Eggs pale yellow, deposited on the under surfaces of leaves 4. 



4. On Cornus (dogwood) comi. 



4. On Rosa (rose) rosae. 



