J. Indian hot. Soc. 50 : 89-100. SPORE MORPHOLOGY OF INDIAN FERNS—X : DAVALLIACEAE AND OLEANDRACEAE^ By S a n t h a D evi a n d B. K. N a y a r * National Botanic Gardens, Lucknow A bstr a c t Spore morphology is described of 31 species (19 belonging to Araiostegta, Davallia, Davallodes, Gymnogrammitis, Humala and Leucostegia of the Davalliaceae, and 12 to Arihropterix, Nephrolepis and Oleandra of the Oleandra-ceae), based mainly on acetoiysed preparations and supplemented by observations on untreated spores. The spores are of the monolete bilateral type and ranging in average size from 26x45 li to 44x78 (i in the Davalliaceae [more commonly ca. 32x65 i;.) and ra. 20x33 (i in Nephrolepis, 26x35 [i in Oleandra and 32x 43 n in Arihropieris. The exine is 2'5—3 (i thick and commonly subverrucate—areolate to tuberculate in Davalliaceae (granulose in Gymnogrammitis), smooth in Arthrop- leris and Nephrolepis and spinulose in Oleandra. A perine is absent in the Davalliaceae ; in Oleandraceae the spores are perinate. The perine is commonly smooth in Nephrolepis (spinulose in N. undulata), granulose in Arthropteris and spinulose to spinose in Oleandra ; it is closely adherent to the exine (sometimes indistinguishable) in most spccies of Nephrolepis and loose in others. It is concluded that the separation of Davalliaceae and Oleandraceae as two distinct taxa is justified, that Nephrolepis is possibly the more primitive and Oleandra comparatively the most advanced among the Oleandraceae, and that Cymnogram- miiis represents the more primitive element in the Davalliaceae. I ntroduction communication attempts to describe the spores of the Davalliaceae and Oleandra­ In a series of earlier communications ceae (together included in the Davalliaceae we described the spore morphology of the by Copeland, 1947), and includes nine major groups of ferns with particular refer­ out of the dozen or so genera included in ence to the Indian species. The present the group. The methods of study as well as of spore description are the same as in 1. Accepted for publication on August 28, earlier communications. The descriptions 1970. 2. Department of Botany. Calicut Univer­ are based on acetoiysed preparations sity, Kerala. mounted in glycerine jelly; notes are added It is a pleasure to record here our grati­ where unacetolysed spores have some tude to Mr. Neil D. Hall of the American Fern characteristic differences from the aceto­ Society, who supplied us several of the spore iysed ones. All measurements recorded samples used in this study. We are thankful also to the authorities of the California Univer­ are the averages based on 10-20 read­ sity Botanical Garden for kindly supplying u& ings in each plane, of spores selected some spore samples. at random. The terminology used is the same as in the earlier papers of this series thicker than nexine, subverrucate-areolate and as described by Nayar (1964). A with verrucae ca. 4 p. across at the complete description is given only of the base, less than 2 |x tall and becoming faint spores of the first specics mentioned under towards the laesura. Ferine absent. each genus; in cases of subsequent Unacet. nearly hyaline and more or less species, only such details in which they of the same size as acet. differ from the first species are mentioned. A. pulchra (Don) Copel. 1805; Natl. Shape of the spore in both lateral and Bot. Gdns. Herbarium; B. K. Nayar polar Views are recorded (the abbreviations 51895. ‘lat’ and ‘pel’ stand for lateral view and Spores 44 (48—4) X 76 |x (range 40 X 68 polar view respectively). To denote to 48 X 88 n) in size. Laesura 26 |ji long, acetolysed and untreated spores the tenuimarginate. Exine 4 |x .thick, light abbreviations ‘acet.’ and ‘unacet.’ are brown. used. The size of the spore is recorded Unacet. 36x 58 [x in size. as polar diameter X longest equatorial Davallia Smith D. canariensis (L.) diameter (for details, see Nayar, 1964). Sm. 1902; Amer. Fern Soc. ex. no. 126 Under each species, reference is made to Spores monolete, bilateral, concavo- the source from which spore sample is convex (lat), elongate-oblong (pol) and 32 obtained for study so as to facilitate cross (36—4) X 52 n (range 28 x 50 to 36 X 56 n) checking if necessary; where samples are in size. Laesura 24 jx long and faintly from herbarium material the name of the crassimarginate. Exine 3 (x thick, light herbarium and the collection number of reddish-brown; sexine much thicker than the specimen are quoted. Several samples nexine, faintly areolate with the areoles were supplied by the American Fern 1 [X tall, 2-3 (X across, irregularly Society’s Spore Exchange Department polygonal, with rounded outer surface and some by the Botanical Garden of the and progressively smaller and fainter California, University, Berkeley. The towards the laesura. Ferine absent. first number quoted in brackets after the Unacet. 28 x 48 jx in size, hyaline to ;iame of each species is the serial number light golden-yellow in colour and with of the spore slide from which observations pale yellowish dense contents. are made; the slides are deposited in the D. chaerophylloides (Foir.) Steud. Sporothek of the National Botanic 1477; Sierra Leone Herbarium, Njala; Gardens, Lucknow. F.C. Deighton 5117. Spores plano-to concavo-convex (lat), D avalliaceae oblong (pol) and 42x68 jx in size. Laesura faintly incrassate. Exine deep Araiostegla Copel. A. hymenophyl- reddish-brown, subverrucate-areolate with loides (Bl.) Copel. 1897; cult., Univ. the verrucae less than 1 |x tall, 4 |x across, Calif. Bot, Gdns., Berkeley U. S. A. irregularly circular to polygonal in outline Spores monolete, bilateral, concavo- and progressively less prominent towards convex (lat), elongate-oblong (pol) the distal pole. Many aborted spores and 34 X 50 [J. (range 28 X 44 to 40 X 60 fx) occur. in size. Laesure 23 jj. long and incrassate. D. cornlculata Moore 1900; Amer. Exine 3 p, thick, light reddish-brown to Fern Soc. ex. no.l29. Fig. 11, nearly hyaline in colour; sexine much Spores ovate (pol) and 30 X 52 |x (range 24 x 48 to 3 2 x 5 6 (x) in size. Laesura subverrucate-areolate with the verrucae tenuimarginate and sometimes forked at 4-6 (X broad. the tip. Exine 4 thick (nexine with a Unacet. nearly hyaline in colour and yellowish tinge), subverrucate-areolate containing a few large, nearly colourless with the verrucae 3-6 (x across and 1 (x plastids. tall. D. fijienslt Diels 1661; Amer. Fern Unacet. nearly of the same size as acet., Soc. ex. no. 89 . light yellowish with a greenish tinge, Spores piano- to slightly concavo-convex containing a few small light-green plastids (lat), oblong (pol) and 42 x 56 (x (range and with the exine appearing nearly 36 X 52 to 44 X 64 jx) in size. Laesura 22 |x smooth, long and incrassate. Exine subverrucate- D. denticulata (Biirm.) Mett. 1664; areolate with the verrucae prominent, Sarawak Museum, Kuching; W.M.A. nearly circular, uniform, deeper in colour Brooke 8052. than the exine, ca. 8 [x across and 2 (i Spores piano- to slightly concavo-convex tall. (lat), oblong (pol) and 32x52 [j. (range Unacet. ra. 34x50 jx in size, hyaline 2 7 x43 to 3 2 x 5 4 [j.) in size. Laesura in colour and containing one to three 22 (X long and faintly incrassate. Exine colourless oil globules and many small subverrucate-areolate with the verrucae plastids. ca. 2 [X tall, 4 |x broad and rather faint D. marieti! Moore 1903; Amer. Fern around the laesura. Soc. ex. no. 352. Unacet. 2 6 x 4 2 (x in size, hyaline in Spores piano- to slightly concavo-convex colour and containing one or two nearly (lat), ovate (pol) and 36 (40-4) x 58 [x hyaline oil globules and a few small (range 3 6 x 5 6 to 4 0 x 6 0 (x) in sizei plastids. Laesura 22 [x long and tenuimarginate. D. divaricata Bl. 1647; Amer. Fern Exine 3‘5 (x thick, dull brown with a Soc. ex. no. 269. Fig. 4. blackish tinge, and areolate with the Spores piano- to slightly concavo-convex areolae often polygonal in surface view, (lat), ovate to elliptic (pol) and 37x60 [x with nearly straight sides, usually 4 jx (range 3 2 x 4 8 to 4 4 x 6 8 jx) in size. across, 3 jx tall, more prominent towards Laesura 30 [x long and tenuimarginate. the distal side and very faint around the Exine nearly hyaline to very pale brownish laesura. , and densely verrucate, with the verrucae Unacet. nearly of the same size as acet., 6 (X across, 2-3 (x tall, subhemispherical hyaline in colour and with dense yellow, and uniform all over. contents. Unacet. 24x42 (x in size, nearly hyaline D. multidentata (W all) Hooker 1867; in colour and with dense yellowish contents cult., Natl. Bot, Gdns., Lucknow. including a few small plastids. Spores piano- to slightly concavo- con­ D. d itsecta J. Sm. 1669; Bogor vex (lat), elongate-oblong to ovate (pol) Herbarium, Indonesia; J. A. Lorzing and 32x48 (x (range 24x44 to 40x52(x) 8953. in size. Laesura 18 (x long and faintly Spores piano- to slightly concavo- crassimarginate, Exine 2'5 (x thick, deep convex (lat) oblong (pol) and 44 x 62 (x brown with a darkish tinge and subverru­ (range 3 6 x 4 0 to 4 8 x 6 8 (x) in size. cate-areolate with the verrucae ca. 4 Laesura 22 [i long and incrassate. Exine across at the base. Unacet. ca. 26 x 40 t* in size with the verrucate-areolate with the verrucae less exine hyaline in colour and contents than 1 tall and ca.