286 W. H. Patton on the Genus Macropis. 



XXXI. — Observations on the Genus Macropis. 

 By W. H. Patton*. 



Hermann Muller found the females of the European 

 Macropis labiata, Panz., upon the flowers of Lysimachia vul- 

 garis only, while the males occurred also upon the flowers of 

 (Enanthe Jistulosa, Rhamnus frangula, and Rubus fruticosusf. 

 This is the basis upon which Sir John Lubbock has made 

 and repeated the statement, that " the species visits exclu- 

 sively Lysimachia vulgaris" $. Yet Dufour had previously 

 taken both sexes upon Alisma Rlantago, and Schenck had 

 taken either one or both sexes upon Bryonia, Rubus ccesius, 

 Circium arvense, and JPicris. Subsequently Mr. John B. 

 Bridgman has taken the male upon Cirsium arvense^ and 

 upon Lysimachia, Mint and Marsh Potentilla, and the female 

 upon Circium arvense and Lysimachia ||. I have taken the 

 female of the American species upon Lysimachia ciliata 9 ^, 

 Rhus glabra and R. typhina, and Archangelica hirsuta, and 

 the male upon Rubus villosus and Cornus paniculata. 



Yet there appears to be some peculiar relationship between 

 the Macropis and the Lysimachia. Collecting in 1874 and 

 1875, I observed that the females taken upon other flowers had 

 no pollen masses upon their legs, and were indeed upon 

 another quest. Mr. Bridgman (7. c. 1878, p. 22) observed 

 that the females taken on Cirsium arvense had no pollen. 

 Can it be that the young live upon the pollen of Lysimachia 

 only, just as other insects are restricted to the foliage of par- 

 ticular plants ? 



Hermann Muller (I. c. p. 248), observing that the pollen 

 was collected upon the tibiae of these bees in thick moist balls, 

 and unable to find any honey in the flowers of Lysimachia 



* Front Silliman's 'American Journal,' Sept. 1879, pp. 211-214. 



t 'Die Befruchtung der Blrnnen durch Insecten,' pp. 348 and 463 

 (1873). 



X Belfast Address, 1874 ; < Nature/ vol. x. p. 425, and ' British Wild 

 Flowers in Relation to Insects,' p. 21 . The inconsistency of his state- 

 ment appears when he says ('British Wild Flowers,' p. 12G) that " Lysi- 

 machia vulgaris produces no honey ;" and the question arises in the mind 

 of the reader, where do the bees get the honey upon which they must 

 live? 



§ Newman's ' Entomologist,' Aug. 1876, p. 158. 



|| Ibid., Jan. 1878, vol. xi. p. 22. 



% The group of Lysimachias containing L. ciliata has recently been set 

 apart as a distinct genus, Steironema, Raf., by Prof. Gray (Proc. Am. 

 Acad. vol. xii. p. 62) because of differences in the Aestivation of the 

 corolla; but for our present purposes, Tridynia (containing stricta and 

 quadrifolia), Lysimachia (containing vulgaris), and Steironema may be 

 treated together under the name Lysimachia. 



