examined on another heath with the same result, but here hive-bees were sucking through the holes.  This case is all the more remarkable, as the innumerable holes had been made within a fortnight, for before that time I saw the bees everywhere sucking in the proper manner at the mouths of the corolla.  In an extensive flower-garden some large beds of Salvia grahami, Stachys coccinea, and Pentstemon argutus (?) had every flower perforated, and many scores were examined.  I have seen whole fields of red clover (Trifolium pratense) in the same state.  Dr. Ogle found that 90 per cent of the flowers of Salvia glutinosa had been bitten.  In the United States Mr. Bailey says it is difficult to find a blossom of the native Gerardia pedicularia without a hole in it; and Mr. Gentry, in speaking of the introduced Wistaria sinensis, says “that nearly every flower had been perforated.” (11/12.  Dr. Ogle ‘Pop.  Science Review’ July 1869 page 267.  Bailey ‘American Naturalist’ November 1873 page 690.  Gentry ibid May 1875 page 264.)

As far as I have seen, it is always humble-bees which first bite the holes, and they are well fitted for the work by possessing powerful mandibles; but hive-bees afterwards profit by the holes thus made.  Dr. Hermann Muller, however, writes to me that hive-bees sometimes bite holes through the flowers of Erica tetralix.  No insects except bees, with the single exception of wasps in the case of Tritoma, have sense enough, as far as I have observed, to profit by the holes already made.  Even humble-bees do not always discover that it would be advantageous to them to perforate certain flowers.  There is an abundant supply of nectar in the nectary of Tropaeolum tricolor, yet I have found this plant untouched in more than one garden, while the flowers of other plants had been extensively perforated; but a few years ago Sir J. Lubbock’s gardener assured me that he had seen humble-bees boring through the nectary of this Tropaeolum.  Muller has observed humble-bees trying to suck at the mouths of the flowers of Primula elatior and of an Aquilegia, and, failing in their attempts, they made holes through the corolla; but they often bite holes, although they could with very little more trouble obtain the nectar in a legitimate manner by the mouth of the corolla.

Dr. W. Ogle has communicated to me a curious case.  He gathered in Switzerland 100 flower-stems of the common blue variety of the monkshood (Aconitum napellus), and not a single flower was perforated; he then gathered 100 stems of a white variety growing close by, and every one of the open flowers had been perforated. (11/13.  Dr. Ogle ’Popular Science Review’ July 1869 page 267.  Bailey ‘American Naturalist’ November 1873 page 690.  Gentry ibid May 1875 page 264.) This surprising difference in the state of the flowers may be attributed with much probability to the blue variety being distasteful to bees, from the presence of the acrid matter which is so general in the Ranunculaceae, and to its absence in the white