NATURAL SCIENCES OP PHILADELPHIA. 83 



4. M. cyanea (Say), J. Acad., iii. 433; Hecate, Newm. Ent., p. 77. 



In shape like M. vittata, but entirely unicoloroiis, bluish or 

 brassy-tlaek ; ely tral punctures deep and regular ; interstices not 

 elevated ; last ventral segment red on each side. L. .22-.24. 

 Middle and Western States, Colorado. 



5. M. excavata (Oliv.), 1. c. f. 29 ; Erebics (Newm.), I. e. ; Pluto (Newm.), I. e. 



Smaller than the preceding, similarly unicolorous ; alternate 

 interstices elevated, punctures very large subconfluent; under 

 side unicolorous. 



6. M. porcata (Mels.), Pr. Acad., iii. 161. 



Entirely dull black, rather parallel ; antennre short ; thorax 

 coarsely punctate ; elytra with the alternate interstices costate ; 

 the third pair of striae confused thi'oughout their length, forming 

 two distinct pairs at their apex. L. .12. -.13 Pennsylvania, 

 Illinois. 



7. M. Melsheimeri, sp. n. 



Short, subquadrate, antennre very short ; coloration precisely 

 that of A.i'osea; (Aytvix 10-striate; alternate interstices acutely 

 costate. L. .13. Pennsylvania. 



8. M. plicatula (Fab.), Syst. El., ii. 63. 



Black, front of thorax, scutellum, base of femora, and of an- 

 tennae orange; surface rugulose and plicate in every direction, as 

 in Chlamys. L. .20. Southern States. 



