W. B. Turrill, 253 OBSERVATIONS ON THE PERIANTH IN CORONARIA. BY W. B. TUKRILL, B.SC. [WITH THREE FIGUKHS IN THK I EXT.]

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1 W. B. Turrill, 253 OBSERVATIONS ON THE PERIANTH IN RANUNCULUS AURICOMUS AND ANEMONE CORONARIA. BY W. B. TUKRILL, B.SC. [WITH THREE FIGUKHS IN THK I EXT.] 'T^HE origin of the perianth in the Angiosperms has already - been discussed from different points of view hy Worsdell (1) and Rendle (2) in an early volume of this journal and it is unnecessary to recall in detail the theories which are there dehated. The two extreme views are that the perianth has been derived entirely and directly from either the bracts or the stamens. Compromising suggestions are that the calyx has been derived from bracts and the corolla from stamens, and that the perianth in some group or groups of plants has arisen by metamorphosis of bracts and in other groups by metamorphosis of stamens. Genera and species of Ranunculaceae have frequently heen mentioned in the controversy, especially by those who have accepted the staminoid origin of the perianth, and it seems worth while to record some observations made this spring on flowers of Ranunculus auricoiiius and also to describe an anomalous specimen of Anemone coronaria recently received at Kew. Ratiuiiculus auricomus is a species of buttercup common throughout a large part of E urope and known from most parts of the British Isles except the extreme north of Scotland. A large patch grows in the shade under a walnut-tree north of the Aroid House in Kew Gardens, and last May the opportunity was taken of making a careful examination of some hundreds of flowers. The results may be most conveniently summarized as follows: 1. The majority of the flowers had no petals (" honey leaves " of PrantI) or staminodes. In such flowers five sepals were constantly present. 2. The normally developed sepals were greenish-yellow with a deeper tinge of green towards the apex, or green with a yellow margin ofgreater or less width, they had no trace ofa nectary and were always hairy on the back and glabrous on the inner (upper) surface. 3. The fully developed petals were bright deep yellow in colour, quite glabrous on both surfaces, and eacb was provided on the inside a short distance above tbe base with a small, ovalorbicular, shallow pit which served as a nectary.

254 W. B. Turritt, 4. The stamens had a relatively broad connective and 2-lobed anthers, each lobe havingtwo pollen-sacs and dehiscing longitudinally. 5.

2 254 W. B. Turritt, 4. The stamens had a relatively broad connective and 2-lobed anthers, each lobe havingtwo pollen-sacs and dehiscing longitudinally. 5. A few flowers were found which were functionally female. These were usually situated low down on the plants and were therefore more or less covered by foliage and by taller plants. Their stamens were very much reduced in size and produced little or no pollen. Similar unisexual states of both Ranunculus bulbosus and R. acris bave been found on the lawns at Kew. 6. A series of interesting transition stages between stamens and petals were found and a selection are here figured. It will be noted that the filament is usually very short or entirely suppressed. Pig. la, is a normal stamen with two of the four pollen-sacs showing. Pig. 1, b represents a staminode from a flower with five ordinary jjreen sepals and no petals. The staminode was short, narrow, and showed clear indications of two anther-lobes each with two pollen-sacs which dehisced by a common longitudinal slit setting free a small amount of pollen. Pig. \,c is very similar to the last but the pollen-sacs are not so well developed and only a little incomplete pollen was found at the base. Pig. l,dissl staminode from a flower with flve sepals and one fully developed petal. One anther-lobe was complete and had two pollen-sacs which produced a small amount of pollen, the other was formed below but was replaced above by a small pocket. Pig. 1, e represents a staminode from a flower with five sepals and one normal petal. In side view it strongly recalls the honeyleaves of species of Helleborus and Eranthis. No pollen was produced and both anther-lobes ended above in pockets. Pig. 1,/ is a staminode taken from aflowerwhich also possessed flve sepals and one normal and one nearly normal petal. A double pocket was present in the lower half and near the base there was an indicatation of a nectary. Pigs. l,g and /(are staminodes from aflowerwhich also had flve sepals and one normal petal. Some incomplete pollen grains were found near the margins. Pig. 1, MS a staminode from a flower which also had four sepals and one normal petal. No pollen grains were found. Pig. 1,7 represents a staminode which may be termed a petal, for a nectary is present near the base and no pollen was produced though the remnant of one of the anther-lobes was present. Pig. 1, k from a flower with flve sepals, is a petal with a wellformed nectary but with thickened ridges parallel to the margins in the lower half.

3 Ranunculus Auricomus and Anemone Coronaria. 255 Fig. 1, / represents a fully developed petal. 7. It was frequently noticed tliat when only four sepals were present the place of the fifth was taken hy a moi e or less normally formed petal. It was always the sepal innermost in the whorl which was thus replaced. 8. In one flower with four normal sepals and no normal petals or staminodes a periantli-leaf, half sepaloid, half petaloid, was found occupying the position of a fifth sepal and internal to the others, Fig. 2, tn. The lower part was green, externally hairy, and sepaloid, the upper yellow, glabrous, and petaloid. There was no trace of a nectory. 9. In one flower, which unfortunately had partly fallen to pieces when gathered, one of the sepals was leplaced by a leaf intermediate between a sepal and an involucral bract. It was greenish-yellow and hairy on the back only, like the sepals, but was regularly lobed (Fig. 2,«). Specimens of Anenioiie coronaria with a fully developed sepal in the position of a segment of the involucre have several times been reported in cultivated plants, but no previous record has been found of the occurrence of this abnormality in wild specimens. Anemone coronaria is a native of South Europe and the Orient. In Palestine it is one of the commonest and most beautiful of the native flowers, and is probably the " lilies of the field " of the FIG. I. Ranunculus auricomus. Transition forms between stamens and 'petal," (I, normal stamen, I, normal " petal,"

4 256 Ranunculus Auricomus and Anemone Coronaria. Fio. 2. Ranunculus auricomus. m. Transition forms between " petal " and "sepal," n, bract-like sepal. Fig. 3. Anemone coronaria. Displacement of " sepal " into the involucral whorl. Bible. The majority of the flowers have from six to nine deep scarlet petaloid sepals and no petals. From 1 to 6 cm, below the flower an involucre is situated and usually consists of three separate hracts which are deeply and irregularly lobed. Amongst a consignment of well dried specimens of this species collected in Central Palestine by Capt. G. H. Ofjilvie was found one which shows a sepal, normal in size, colour, venation and indumentum, but arising in the involucral whorl 2 cm. below the remaining nine sepals of the flower, Fig. 3. One of two explanations is possible, that a sepal has become misplaced, its primordium having been left behind when the pedicel above the bracts lengthened, or tbat an involucral bract has become abnormally metamorphosed into a sepal. The former seems the more probable because three norma) bracts are present in the involucral whorl in addition to the sepal. REFERENCES. 1. Worsdell. " The origin of the perianth of flowers." New Phytoloeist 2, pp. 42, 116, Rendle. " The origin of the perianth in seed-plants." I.e., p Davis. Knuth's " Handbook of flower pollination." 2, pp ,

ACURIOUS malformation in one of the flowers on a raceme of

ON AN ABNORMALITY IN PURPUREA By VIOLET L. ANDERSON. DIGITALIS Quain Student of Botany, University College, London. (With 6 figures in the text.) ACURIOUS malformation in one of the flowers on a raceme