250 TRANS. ST. LOUIS ACAD. SCIENCE. 



tongues, follow : Bombus muscorum, tongue of female 13-15 mm., 

 male 12-13 im^i-r worker 9-10 mm. Melampyrum yiemorosum, 

 tube of corolla 18-20 mm. Bombus Rajellus, tongue of female 13 

 -14 mm., male lo-ii mm., worker 11-13 mm. The nectariferous 

 spur of Dicentra spectabilis. is 18-20 mm. long. Bombus lapida- 

 rius, tongue of female 12-14 mm., male S-iomm., worker 10- 

 12 mm. Three flowei s are perforated by it : Symphytum officinale, 

 corolla 14 mm. long; Melampyrum prafense, i^)-i5 mm. long; 

 M. nemorosum, iS 20 mm. long. Seven flowers are perforated by 

 Bombus pratorum. Dicentra spectabilis, Melampyrum nemorosum^ 

 M. pratense, and Rhinanthiis major ; in the latter the tube of the 

 corolla is lo-ii mm. long. The tongue of a female was 12-14 5 

 mm. long, male 8-10 mm., worker S-i2mm. In Symphytum 

 officinale and Trifolium pratense, the tube of the corolla is 9-10 

 mm. long. 



The tongue of a female of Bombus tcrrestris was 9-1 1 mm. long, 

 and of a worker 8-9 mm. In the Alps it visits 85 species ; 54 are 

 strictly alpine. Ten difterent species are perforated ; 6 of thi& 

 number are strictly alpine. Miiller, in his " Befruchtung der 

 Blumen," records its visits to 79 species ; out of these, 17 are 

 perforated. It perforates such flowers as Aquilegia vulgaris, 

 where the nectariferous spur is 15-22 mm. long. In Pedicu- 

 laris sylvatica the nectariferous tube is 10-14 mm. long; Gale- 

 obdolon luteuiii 8 mm. long ; Galeopsis Tetrahit 11 -17 mm. 

 long ; Nepeta Glechoma, in small-flowered form 6. 5-8 mm. 

 long, in large-flowered form 14-16 mm. long. While this spe- 

 cies perforates a great many flowers, Bombus mastrucatus 

 opens those of no less than 34 difterent species out of 76 which 

 it visits ; 36 of these are strictly alpine. The tongue of a female 

 measured 10-12.5 mm., of a worker 9-10 mm. So intent is this 

 insect on its malicious work that it perforates many flowers where 

 the nectar is easily accessible, as in Anthyllis vulneraria in which 

 the tube of the corolla is 9-10 mm. long; Trifolium pratense and 

 its var. niva e 9-10 mm. In Salvia pratensis it is hardly 8 mm. 

 long ; in Yicia cracca 5-6 mm. long. From the above is seen 

 that Bombus mastrucatus, B. terrestris, B. pratorum, to which must 

 be added Xylocopa violacea, are the principal perforators of Eu- 

 ropean flowers. The second is one of the commonest of Euro- 

 pean humble-bees. The first is found principally in the Alps, 



