Vegetable Teratology. Maxwell T. Masters

Vegetable Teratology - Maxwell T. Masters


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isolation or separation of different whorls that are ordinarily adherent together is by no means of rare occurrence. Were it not that the isolation is often congenital, the word detachment would be an expressive one to apply to these cases, but as the change in question occurs quite as often from a want of union, an arrest or stasis of development, as from a bonâ fide separation, the word solution seems to be, on the whole, the best. It corresponds in application to the word liber (calyx liber, &c.), in general use by descriptive botanists. As here employed, the term nearly corresponds with the "adesmie hetérologue" of Morren. Moquin Tandon does not make any special subdivision for the class of cases here grouped together, but places them all under "Disjonctions qui isolent les organes." It seems, however, desirable to have a separate word to express the converse condition of adhesion, and for this purpose the term solution, as above stated, is here employed. Diagrammatically, the condition may be expressed by placing a dotted line at the side of the letters thus:

      : S S S S S :

       : C C C C C :

      would indicate the disjunction of the sepals from the carpels (c), in contradistinction to adhesion, which may be represented by the unbroken line thus:

      | S S S S S |

       | C C C C C |

      Solution of the calyx from the ovary.—Of all the instances of adhesion which take place under ordinary circumstances, that between the calyx and the ovary is perhaps the most common. The calyx adhærens or superus is a structural characteristic to which all botanists attach considerable importance; so that when exceptional cases occur in which the calyx becomes detached from the ovary, becomes, that is, inferus or liber, a proportionate degree of interest attaches to the irregularity. It is not within the scope of the present work to inquire whether this detachment be real or merely apparent, arising from a want of union between parts ordinarily united together. This point must be left to the organogenists to decide in each particular case. So also the question as to what share, if any, the expanded and dilated flower-stalk may take in what are usually called inferior ovaries, can be here only incidentally touched upon.

      Fig. 35.—Proliferous Rose. Showing an absence of the usual dilatation of the flower-stalk, and other changes.

      Fig. 36.—Section through Apple blossom, showing detachment of calyx from ovaries, absence of dilated flower-stalk, &c.

      Fig. 37.—Calyx detached from carpels in Apple.

      On the other hand, M. Planchon's specimen of the Quince before alluded to, not to mention other instances, tends to show that the bases of the sepals do sometimes enter into the composition of the pome. And, indeed, in many of these cases it would be impossible to say where the axial or receptacular portion ended, and the foliar portion began. As both from normal organogeny as well as from unusual conformation contradictory inferences may be drawn, it would obviously be unsafe to attempt the explanation of the so-called calyx-tube in general from any particular instances; so far as Rosaceæ are concerned, there is so much variation in the relative position of calyx and carpels under ordinary circumstances, that it is no matter for surprise that similar diversities should exist in teratological cases. A similar remark will apply to Saxifragaceæ, Cucurbitaceæ, Myrtaceæ, Bruniaceæ, Rubiaceæ, and other families of like conformation.

      Fig. 38.—Flower of Œnanthe crocata, in which the five sepals were completely detached from the ovaries, here three in number and destitute of stylopods.

      In Umbelliferæ, a detachment of the calyx from the ovaries frequently occurs, sometimes without any other change; at other times attended by more serious alterations. So far as can be judged from exceptional occurrences of this kind, it would appear that in this order the axis or flower-stalk does not, in any material degree, enter into the composition of the fruit.

      In the Rubiaceous genus Bikkhia, as mentioned by Duchartre, the ovary is completely inferior, but when the fruit arrives at maturity four small leaves are detached from its surface which had previously adhered to it, and which it seems reasonable to consider as the sepals.

      In Onagraceæ (Jussieua), as also in Cactaceæ (Opuntia), buds have been observed on the surface and edges of the inferior ovary. Indeed, in the former genus, they have been produced artificially, but as buds may be formed on foliar as well as on axial organs, the fact cannot be made great use of in support either of the foliar or axial nature of the inferior


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