THE THREE FORMS OF I.TTHBTIM SALTCARIA. 175 



Insects are neccssan- for the fertilization of this Lytlirum. 

 During two years I kept two plants of each form protected, and 

 in the autumn they presented a remarkable contrast in appear- 

 ance with the adjoining uncovered plants, which were densely 

 covered with capsules. In 1863 a protected long-styled plant pro- 

 duced only five poor capsules ; two mid-styled plants produced the 

 same number ; and two short-styled plants between them produced 

 only one : these capsules contained very few seed ; yet the plants 

 were fully productive when artificially fertilized under the net. 

 In a state of nature the flowers are incessantly visited for their 

 nectar by hive- and liumble-bees and various Diptera. The nectar 

 is secreted all round the base of the ovarium ; but a passage is 

 formed along the upper and inner side of the calyx by the lateral 

 deflection (not represented in the diagram) of the basal portions 

 of the filaments ; so that insects invariably alight on the upper 

 side of the flowers, on the projecting stamens and pistil, and insert 

 their probosces along the ujjper inner margin of the calyx. "We 

 can now see why the ends of the stamens with their anthers, and 

 the ends of the pistils with their stigma, are a little upturned, in 

 order that they may brush against the lower hairy surfaces of the 

 insects' bodies. The short stamens which lie enclosed within the 

 calyx of the long- and mid-styled forms can be touched only by 

 the proboscis and the narrow chin of the sucking bee ; hence they 

 have their ends more upturned, and they are graduated in length, 

 so as to fall into a narrow file, three deep, sure to be raked by 

 the thin intruding proboscis. The anthers of the longer stamens 

 stand laterally further apart and are more nearly of the same 

 length, for they have to brush against the whole breadth of the 

 insect's body. I may here incidentally remark, that in very 

 many flowers the pistil, or the stamens, or both, are rectangularly 

 bent to one side of the flower : this bending may be permanent, 

 as with Lytlirum and many others, or may be efiected (as in 

 Dictamnus fraxineUa and many others) by a temporary move- 

 ment which occurs in the stamens when the anthers dehisce, 

 and in the pistil when the stigma is mature ; but these two 

 movements are by no means always contemporaneous in the 

 same flower. iN'ow I have found no exception to the rule, that 

 when the stamens and pistil are bent, the bending is exactly to 

 that side of the flower which secretes nectar (even though there 

 be a rudimentary nectary of large size on the opposite side, as m 

 some species of Cori/dalis) ; or, when nectar is secreted on all 

 IIKN. PBOC. — BOTAirr, TOI. Till. ^ 



