THE CONTRIBUTIONS of Masters to study of morphologically important but much neglected family, Passifloraceae (1871, 1872), are comprehensive and elaborate but deal pritnarily with external morphology and taxonomy and touch upon vascular anatomy of flower only superficiallv. Moreover, they were made long ago and parts thereof now need revision and confirmation. The interest of author in family, as has already been pointed out (Puri, 1945), was aroused chiefly by presence of inverted placental strands in ovary wall. The beautiful corona, which has failed to attract attention in recent vears, also seemed to me to present a promising problem for study. The observations recorded and interpreted here deal with sepals, petals, stamens and carpels; corona, and structures associated with this structure,, will be considered in next paper of series. As will be evident from following account, study emphasizes role of vascular anatomy in illucidating nature of floral parts. MATERIAL AND METHODS.-Material of certain genera that were considered important from point of view of present study unfortunately could not be secured. In all only about twelve species of Passiflora could be collected and studied. Material of Passiflora tucumanensis Hook. was collected in Botanical Garden of MIeerut College;_ that of suberosa L. and L. from Dacca and Simla respectively. Alcohol-preserved material of capsularis L., holosericea L., suberosa, var. minima, and racemosa Brot. was obtained through courtesies of Dr. N. L. Bor and Mr. M. B. Raizada of Forest Research Institute and College, Dehra Dun. Some alcoholpreserved flower buds of a species of Passiflora (named P. coerulea in Taj Gardens, Agra, but apparently incorrectly as it differs from my material of coerulea, which was identified by Sibpur Botanical Garden, Calcutta) were very kindly passed-on to me by Prof. N. M. Mukerji of Agra. Herbarium material of mollissirma (H.B.K.) Bailey, lunata Wild., and leschenaultii Hook. was very kindly given me by Prof. Natesan of Presidency College, Madras. Serial microtome sections, both transverse and longitudinal, were cut and stained with crystal violet and erythrosin. Obserivations recorded here are mainly based on these. Occasionally hand sections and mounts of entire flowers cleared in xylol were also found helpful in understanding of gross anatomy and relation of parts. 'Received for publication February 17, 1947. While not claiming support of Dr. Maheshwari for any of views expressed herein, author wishes to express his gratefulness for his unfailing interest in him in general and in his work in particular. EXTERNAL MORPHOLOGY.-A brief description of floral morphology, based in part on Engler and Prantl (1925) is useful in understanding of anatomical account that follows. The Passifloraceae is a small family comprising 11 genera and some 580 species of which a majority belong to genus Passiflora. The species inhabit chiefly warmer parts of America, tropical Africa, Asia, and Australia. With exception of Adenia, all are monoecious. The name Passiflora is said to have been coined by Roman Catholic missionaries who fancied they saw the crown of thorns in fringes of flower, nails in styles with their capitate stigmas, hammers to drive them in stamens and cords in tendrils. The bracts.-The occurrence of three bracts below each flower is an almost constant feature of Passiflora. The bracts may be minute and linear, as in Sections Decaloba and Cieca, or large and leaf-like, as in Granadilla and Calopathanthtis. They are always sessile and spirally arranged just below receptacle (fig. 1, O-R). They are mostlv free but in mollissima they are fused into a long tube. In Passiflora sp., collected in Taj Garens, each bract has a number of nectaries arranged along upper part of its sparingly serrate margin (fig. 1, R). The sepals.-There are five more or less thick and leathery sepals which usually have a midrib that is sometimes sharply defined (fig. 2, K-N). In capsularis some of lateral veins also are encased in prominent ribs (fig. 1, J). The overlapped edges are generally thin and meinbranous and may be petaloid (fig. 4, G). The apices of sepals present features of some morphological significance. The prominently bulging midrib becomes free as a horn-like process, corniculus, which extends beyond tip of (fig. 3, J-N). The is curved inward, forming a more or less dome-shaped structure that in transverse section resembles a signet ring (fig. 3, M). In figures this is labelled sepal sheath. The petals.-Occurring within, and alternating with, sepals are five petals, which are generally smaller and more delicate than former (fig. 1, J; 2, K). Petals are wanting in Sub-section Eutryphostemma of Tryphostemma and Sections Chloropathanthus and Cieca of Passiflora. In young condition they merely touch one another by their tips but after some time overlap and in aestivation become imbricate (fig. 3, A). A rudimentary corniculus was observed crowning some of petals also in Passiflora sp. In sections figured, innermost petal has its apex bent inward and downward (fig. 3, D-E); each of next three petals has a rudimentary corniculus (fig.
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