2038 Insects. 



elongate cylindrical abdomen, and by usually having the apex of the 

 clypeus white or yellow. 



To this genus belong some of the smallest species of bees found in 

 this country. These bees appear rather later than those belonging to 

 the genus Andrena, and are found in great abundance from the middle 

 of summer to the end of autumn ; indeed I captured H. quadrinotata 

 last season as late as the 31st of October. The males of some species, 

 particularly those of H. abdominalis, abound during August and Sep- 

 tember. 



These bees are frequently infested by various species of Strepsip- 

 tera, one of which Mr. Curtis has figured and described, in his beau- 

 tiful work on British genera, under the generic name of Halictophagus, 

 from its having been captured in company with the males of a species 

 of this genus (Halictus seratus) : indeed one of the bees captured by 

 Mr. Dale proved to be infested by some species of Strepsiptera : this 

 was as late as the middle of August. I have never met with any of 

 the species of the genus Andrena which were Stylopized so late in 

 the season, but have met with Halicti so infested in the month of 

 August. I possess a female of H. nitidiuscula, one of the smallest of 

 the genus, with the heads of two female Stylops protruding between 

 the third and fourth segments of the abdomen ; it indeed requires the 

 aid of a glass to detect them : the male of this species, I should pre- 

 sume, must be a much smaller species than any yet discovered in this 

 country. The smaller species of bees contain smaller females of Sty- 

 lops, a fact which goes to prove that our knowledge of the number of 

 the species of the Strepsiptera is very limited. 



Upon the bodies of these bees is also found that remarkable crea- 

 ture, the Pediculus Melittae of Kirby, which in form resembles the 

 larva of Meloe, as recently shown by Mr. Newport, in his elaborate 

 and admirable paper on that insect published in the twenty-second 

 volume of the Linnean Transactions. The larva of Meloe is of a 

 bright orange colour, whereas the Pediculus Melittae is black ; and 

 Mr. Newport informs us it is not a larva of either Meloe violaceus, 

 proscarabaeus or cicatricosus ; he supposes it to be the larva of some 

 allied genus, or of some other species of Meloe. The Pediculus Me- 

 littae- is very abundant in some districts : I have found numbers on 

 various species of the Andrenida), and they abound in the flowers 

 which these bees frequent, in situations where only two of the species 

 of Meloe named above are to be met with. 



I once captured a species of Halictus infested with Acari, but I do 

 not think they are very subject to such attacks. Acari appear to me 



