OF WASHINGTON. 243 



Orders this general rule is less strictly adhered to and least of 

 all, I think, in the Coleoptera. Here I cannot point out among 

 the larger families a single one which is strictly nocturnal, and 

 only one, the Buprestidse, is strictly diurnal, while the 

 Chrysomelidse and Coccinellidae are almost entirely diurnal. 

 Among the smaller families several could be mentioned in 

 which the unity in flying habits is adhered to, but in most of 

 the larger families this unity is not maintained, and what, e. g., 

 in a portion of the Lepidoptera is an accessory family character, 

 becomes in most Coleopterous families a character for minor 

 groups, sometimes for tribes or groups or genera or even only a 

 specific character, and sometimes a character of no value what 

 ever, i. e. , many species have the faculty of flying both at day 

 and night time. In general it may be said, however, that in 

 Coleoptera a certain uniformity is maintained for genera and 

 often for higher groups. I have attempted to draw up a list 

 of the Scarabaeidse showing how this biologic character varies 

 in a single large family. If I knew exactly the habit of every 

 species such a list would be of considerable interest, but since 

 I am not acquainted with the flying habits of quite a number 

 of genera, it has remained rather fragmentary and I give it 

 herewith as much condensed as possible : 



'Subfamily Scarab<zid& Laparostidi. The genera are noc 

 turnal, rarely crepuscular, with the following exceptions : Cer 

 tain species of Canthon, Aphodius, At&nius and Trox, which 

 are both day and night flyers. Nicagus is the only strictly 

 diurnal genus of this subfamily, but belongs, perhaps, to the 

 lyUcanidse. 



Subfamily Melolonthidcz . The Laparostict genera, viz : 

 Amphicoma, Oncerus, Chnaunanthus (and no doubt also Podo- 

 lasia) are strictly diurnal. In the Pleurostict genera there is 

 great diversity. Strictly diurnal are : Hoplia, Dichelonycha 

 (and probably Ccenonychd) and Macrodactylus : Hypotrichia 

 is both diurnal and nocturnal. Strictly nocturnal are : Dip- 

 lotaxis (and probably also the genera allied thereto) , Lachnos- 

 terna (with the exception noted above), Listrochelus, Polyphylla 

 and probably also Thyce and Phobetus. In Serica some of our 

 species, viz., 5. vespertina and holosericea are nocturnal, while 

 others, ,S. tricolor, trociformis and at least one of our western 

 species, are strictly diurnal. 



Subfamily Scarab&id<z Pleurosticti. The genera are strictly 

 nocturnal with the exception of Strigoderma and all genera of 

 the tribe Cetoniini excepting Osmoderma. 



In the discussion Mr. Marlatt stated in reply to the statement 

 by Mr. Schwarz that the species especially noted in Utah was 

 observed flying over grass, and in the absence of trees or shrubs 



