212 University of California Publications. [Geology 



Dytiscus marginicollis LeConte. 



PI. 15, fig. 6. 



Specimen No. 10014, Univ. Calif. Col. Invert. Palae. Asphalt beds at 

 Rosemary, near Los Angeles. 



Two elytra of this species are fairly well preserved, but are 

 crushed and flattened, so that the determination was at first 

 difficult, This is one of the water beetles, which are found in the 

 vicinity of streams and ponds throughout our region. They are 

 strong flyers and frequently come to electric lights in the city. 

 It can readily be imagined that this specimen which has been 

 preserved to us was flying over the country in search of a pool 

 or stream, and mistook the tar spring for a pool of fresh water. 



CONIONTIS ROBUSTA Horn. 

 PI. 16, fig. 27. 



Specimen No. 10015, Univ. Calif. Col. Invert, Palae. Asphalt beds at 

 Rosemary, near Los Angeles. 



One elytron half buried in a hard lump of asphalt, but the 

 characters of the above species seem unmistakable. The species 

 of this genus are rather numerous in some parts of Southern 

 California. They hide under boards and in the midst of rubbish 

 and only come out to forage during the twilight and even into 

 the night, so from 'this it can be readily seen how they came to be 

 entrapped in the tar springs. 



Coniontis abdominalis LeConte. 



Specimen No. 10016, Univ. Calif. Col. Invert. Palae. Asphalt beds at 

 Rosemary, near Los Angeles. 



Two fairly well preserved specimens — with the head. The 

 sculpture and striation are practically the same as in the living 

 forms. 



Coniontis puncticollis LeConte. 



Specimen No. 10017, Univ. Calif. Col. Invert. Palae. Asphalt beds at 

 Rosemary, near Los Angeles. 



A portion of an elytron in fairly good preservation, showing 

 the smooth, shining, lightly punctured and striated surface. 



