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Jun 22d /62/ Musk orchis

George has watched large beds for an hour or two & saw numerous extremely minute Hymenopt. visiting the flowers & some diptera. He brought home 5 of these, which had pollinia, in most cases two, firmly attached to end of femur where it joins the coxa, & is therefore prominent like an elbow-joint. These insects must have crawled into the flower with their backs to the labellum; & G. saw several crawling in in this position. (N. B. good to show good of Labellum changing position.) The pollinia were fixed in 3 specs. quite

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symmetrically on the elbows - in one spec. it was fixed at little lower on femur, but yet just reached the coxa.

After depression the ends of pollen-grains projected just beyond the tibia & would readily strike stigma. The discs are attached exteriorly to femora so insect must crawl in between the discs. The insects stopped in flower 2 or 3 minutes.

June 23d. G has watched again, he saw 5 of same insect with attached pollinia & brought home 3: these each had one; fixed exactly as before, except one had it fixed on inside of femur. He saw many entering, some back downwards, some laterally or irregularly; but several of them came out & turned themselves so as to enter backwards. I can now perfectly understand distance of glands: the insect crosses between, & in backing out, they strike their elbows against the under side, which is bottom of disc - The 2 upper petal & upper sepal help to make flower tubular.

[in margin:] In every case front Legs: because insect can then reach bottom of short nectary

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June 25' George has now visited beds of Musk O. thrice, each time saw many minute Hymenoptera of at least 4 kinds visiting flowers. These have body only 1/20 of inch long. He saw many with pollen-masses & brought home 18 of these several insects with attached pollinia - generally with one - some with 2. The Hymenopt. with ∆ body had in each case two. In 2 of the 18 the disc was attached a little more towards the distal end of femur; in one attached to interior surface. In all other cases attached exteriorly to one or both femora at the base where joined to Coxa. It is wondrous that the flower shd be adapted to these several genera so that pollinia always get attached to same spot. George again saw

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some come out & go in proper direction with back downwards. This show how closely adapted flower is to these small Hymenoptera, in shape & length. Wonderful that in no case attached to other parts of body. Say in every case attached to femur of front limb then give trifling exceptions

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Jun 27' 62 / Musk

The 2 upper petals extremely like Labellum. The latter is very early directed downwards, sometimes laterally, but generally at ∠ of 45 to horizon.

[sketch] upper upper petal Lab

This is probably connected with insect entering in various ways. I mention it because a friend, asked by what steps an orchid with labellum as usual downwards could possibly come to have it upwards

Malaxias is analogous case.

George brought me 6 more Hymenopterous insects (no Diptera) all with pollinia (one alone had 2) attached as usual & one soft-winged Beetle very minute. (Telephorium) with do. This makes 25 insects. Say disc attached always outside of femur & on joint with Coxa. These are of

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4 genera, besides beetle. Size seems governing element; one was seen caught within flower not having been able to withdraw pollinia & this was caught externally to disc. From shape of entrance into very short nectary I fully believe they enter laterally. There is not room between the 2 discs. Hence great majority with only one pollinium - Flower bent at ∠ to ovarium. Accordng to this view they enter between Labellum & either upper petal & this point is either downwards or upwards.

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July 2d. 62 Musk myself.

Two lower sepals lower than upper edges of Labellum rather further apart from edge of 2 upper petals than those from each other.

Lab. & upper petal flat, pointed & alike (we can now understand this unusual fact & oblique position of Labellum) Hence there is transverse passage across flower in line joining 2 lower sepals. Here minute insects commonly enter (do not say much about insects coming out & going in again for I doubt whether G. could have well seen). In middle of this passage is triangular entrance into nectary & insects stand transversely & [sketch] Lab

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insert front legs & head into nectary in withdrawing strike under side. I know this from now having seen 3 insects permanently glued to disc.

To day I caught two minute Dipterous insects with disc glued in same place, & another of the same minute beetle. This makes number 27 - It is very odd passage being [transverse] & oblique with respect to Lab that this point shd be directed downwards. I am not at all surprised I overlooked such atoms of insects; shd never have dreamed they could do work.