l88 CALIFORNIA ACADEMY OF SCIENCES. 



Family MACHILID^ Grassi. 



It is a rather difficult task to try to identify alcoholic 

 specimens belonging to this family. According to Grassi 

 and Rovelli, the following characteristics constitute the 

 species within the only genus of the family: 



i. The length of the antennae and of the median 

 cercus. 



2. The thoracic hump, more or less apparent. 



3. The eyes. 



4. The color of the body. 



5. The shape of the scales. 



As the color is dependent on the scales, which generally 

 more or less fall off, when the insects are laid in spirits 

 of wine, and, moreover, as individuals preserved are 

 rarely found without the antennae and caudal appendages 

 broken off, the difficulty of easy identification will be 

 understood. 



I also have considered it more proper to leave a few 

 Mack Hides as indeterminable. 



Gen. I. Machilis Latreille. 

 Machilis aurantiacus n. sp. 



The head is small . The eye patches are somezvhat more 

 broad than long - , and are contiguous to one another, with 

 three-fourths of the inner margin; on the front margin 

 they are -pinched out. The labial -palpi are four-jointed, 

 and have the tzvo middle joints of about the same length. 

 The maxillary palpi are seven-jointed, and have a small 

 process on each of the tzvo inner joints. The antenna? are 

 not annulated . The cerci are very stiff and dazzling zvhite 

 in color. The color of the animal is orange-tazvny. The 

 cuticula is smooth, with bottle-like figures. Length J mm. 



The antenna being injured in all the specimens, their 

 length cannot be exactly decided. To judge from their 



