NO. 1897. BEES OF THE aENVS OSMIA—COCKERELL. 217 



LIST OF SPECIES. 



[The asterisk (♦) indicates that the species is in the collection of the United States National Museum. 

 Certain few specimens sent to the Museum by Professor COckerell and labeled "cotyi)€s" are considered 

 paratypes, as Professor Cockerell uses the name "cotype" in the sense which the Museum uses "paratype." 

 A good many of the species in the collection are homotypes made by Titus, or were determined by I'rofessor 

 Cockerell. The Museum has a goodly lot of unworked material in this genus, and when this has been deter- 

 mined the niunber of species in its collection will be greatly increased. Of tlie 107 names in the following 

 list, 60 are represented by specimens in the collection. Of these 60, 22 are types or paratypes.— 



S. A. ROHWER.] 



In each case the type-locality and collector of the type is given, ifknown. There 

 are also references to the tables, numbered as in the list above. 



*"abjecta Cresson, 1878. Colorado (Ridings). Tab. 2. 



A black species. 

 *abnormis Cresson, 1878. Colorado (Ridings, Morrison). 



Male with peculiar legs, figiu-ed by Cresson. Trans. Amcr. Ent. Soc., vol. 7, 

 p. 105. 

 albiventris Cresson, 1864. "Conn., New York, Penn." Tab. 4. 



Ventral scopa white, 

 albolateralis Cockerell, 1906. Florissant, Colorado (Cockerell). Tab. 2. 



Possibly the female of 0. cyaneonitens. 

 amala Cockerell, 1907. Florissant, Colorado, June (Rohwer). Tab. 7. 



Additional characters; Canadian Entomologist, 1910. p. 312. 

 *aprilina Cockerell, 1907. Boulder, Colorado, April (W. and T. Cockerell). Tab.l. 



Visits Pulsatilla. Mr. S. A. Rohwer took it at Boulder, May 15, 1908, at flowers of 

 Besseya plantaginea. 



Paratype.— Cat. No. 11919, U.S.N.M. 

 *armaticeps Cresson, 1878. Colorado (Ridings, Morrison). Tab. 1, 2. 

 armaticeps sapellouis Cockerell, 1901. Hill above Beulah, New Mexico (Cockerell). 



Female with cheeks very strongly and quite closely pimctured; mesothorax strongly 

 and densely punctured. Length, 12 mm. 

 *ashmeadii Titus, 1904. Dalles, Oregon. 



Allied to 0. odontogaster, but the male is larger, deeper colored, and has the antennae 

 with the scape black, the flagellum pale testaceous, excepting a black tip to the 

 flattened last joint. 



Type.— Cat. No. 6359, U.S.N.M. 

 *atriventris Cresson, 1864. Connecticut (E. Norton). Tab. 4. 



West to Boulder, Colorado (S. A. Rohwer). Allied to 0. coloradella, but clearly 

 • distinct, 

 atrocyanea Cockerell, 1897. Olympia, Washington State, July (Kincaid). Tab. 

 5, 8. 



Female with hair of pleura, sides of metathorax, and scutellum black, that on scu- 

 tellum with a few pale hairs intermixed; head strongly blue. 



Also in Ormsby County, Nevada (Baker), 

 azteca Cresson, 1878. Mexico (Sumichrast). 



Black; ventral scopa yellow, 

 basilissa Cockerell, 1911. Claremont, California (Baker). 



Magnificent deep purple; pubescence all black, 

 bella Cresson, 1878. Colorado (Morrison). Tab. 3. 



Bright green, 

 bennettse Cockerell, 1907. Boulder, Colorado, May (Mrs. C. Bennett). Tab. 3. 



Brilliant green. Also in California, 

 besseyse Cockerell, 1910. Boulder, Colorado (S. A. Rohwer). 

 botitena Cockerell. 1909. Lee County, Texas, April (Birkmann). 



Ventral Bcopa yellowish-white. Allied to 0. sub/asciata. 



