13. EUCERA. 183 



Only one species of this genus is found in this country ; but 

 about twenty are described as inhabiting Europe ; species have been 

 found in Algeria ; and one has been received from North China. 

 St.-Fargeau mentions one from Cayenne. All the Brazilian species, 

 the males of which have elongate antennae and closely resemble 

 the genus Eacera, belong either to the genus Tetralonia or Melis- 

 sodes, in both of which the anterior wings have three submarginal 

 cells. Klug has described two species from Syria, and Spinola two 

 from Egypt. 



Kirby describes four species belonging to his subdivision of long- 

 horned bees ; his second species, which he names " Knguaria," is 

 a small faded form of Eucera longicornis ; the third, " pollinaris" 

 is a female belonging to the genus Tetralonia of Spinola, and is 

 from the Cape of Good Hope ; the fourth is a species of Melissodes ; 

 it is in a faded and bad condition, but is probably identical with 

 Melissodes denticulata, described by myself in the Catalogue of Hyme- 

 nopterous Insects, part ii. p. 311, and is from North America. Eucera 

 longicornis appears usually in May, and prefers a stiff clayey soil in 

 which to form its burrows ; they are sometimes found in large colo- 

 nies, when numbers of males may be seen on the wing gyrating in 

 all directions over the ground perforated with their burrows : occa- 

 sionally they may be observed to come into contact, when two, 

 three, or four will cling to each other, and get their long antennae 

 so intertwined that they have some difficulty in disengaging them- 

 selves. Their burrows are usually about 6 inches in length : at 

 the end of each an oval chamber is excavated ; it is perfectly 

 smooth within and coated or lined with a liquid secretion by the 

 parent bee, which prevents the mixture of pollen and honey depo- 

 sited in a semifluid state from being absorbed. Each cell is the 

 abode of a single larva, which passes the winter months in that con- 

 dition ; about the month of April the change to the pupa state takes 

 place ; and very shortly afterwards the perfect condition is attained. 

 The pupa is enveloped in a thin transparent pellicle which encloses 

 every limb. On arriving at the mature active state the bee by degrees 

 frees itself from the shroud in which it was enclosed, and comes 

 forth into the open air and sunshine. Immediately on emerging, it 

 passes its antennae through the notch at the base of the first joint 

 of the anterior tarsus, and thus divests those organs of the thin 

 pellicle in which they were enclosed. The long antennae of the males 

 of this and the two allied genera are doubtless adapted to some 

 peculiar phase in the economy of these bees ; and the remarkable 

 hexagonal reticulation which covers their antennae is no doubt an 

 adaptation which is connected with their peculiar function, but which 

 we are as yet unable satisfactorily to appreciate. 



1. Eucera longicornis. 



E. nigra, pallide fulvo villosa, thorace abdominisque basi hirsuto 

 fulvis. Mas antennis filiformibus longitudine corporis. 



