Nelumbo - The Bulletin of the Botanical Survey of India

P. K. Bhattacharyya ¹

Affiliations
1 Burdwan University, Burdwan, IN

Abstract

The vascular cambia of 20 species of the dodder and its allies belonging to the CassythaceaE, Convolvulaceae and Cuscutaceae were surveyed to assess their phenetic and phylogenetic significance. In natural condition all of them contain anomalous cambia. The Cassythaceae bore transitory cambium in the normal position but atypical by asmmetric activity. (The Cambium alternatelt retards accemtuates xylem formation on several segments and there are profuse sehizongenous spaces in wood. Haustoria contains both traheids and vessels).

In stems and ischolar_mains of the Convolvulaceae a series of widely different anomalous cambia were found which sometimes differed in stems and ischolar_mains of the same species. Stems of arborescent group had bands of interxylary phloem in concentric rings, while in the primitive twiners these are arranged in radial plates. In general, a tendency was to increase the proportion of soft tissue. In Cuscutaceae the specified anomaly was the interfascicular cambium. Ray initials were absent but fusiform initials differentiated into profuse parenchyma cells and a few vessel elements.

Haustorium develops only imperforate tracheary elements. The evolutionary history vascular cambium in the Convolvulaceae was mainly one of reduction in activity and area. Thus the vesselless haustorium of Cuscutaceae. may be regarded as a reduced farm in with the vessel bearing haustorium of Cassythaceae. It 1s also concluded that the primitive condition of Cuscutaceae is possibly derived from the general condition of Convolvulaceae.

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P. K. Bhattacharyya ¹

Affiliations
1 Deptt. of Botany, Burdwan University, Burdwan 713104, IN

Abstract

The present paper deals with the first information on the bryophyte flora of Barddhaman district, West Bengal. Altogether 26 species under 18 genera belonging to 13 families have been reported. Each species is appended with relevant field data, necessary illustrations and diagnostic features. Archilejeunea planiuscula (Mitt.) Staph. and Lejeunea boninensis Harikawa are the new records to the known flora of the Indian Union

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P. K. Bhattacharyya ¹

Affiliations
1 Department of Botany, University of Burdwan, Burdwan - 713 104, West Bengal, IN

Abstract

No Abstract.

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P. K. Bhattacharyya ¹, Kaustuv Bhattacharyya ²

Affiliations
1 Department of Botany, University of Burdwan, Burdwan 713 104, WB, IN
2 Govt. College of Education, Banipur, 24 Parganas (N) 743 233, WB, IN

Abstract

A tabular comparison of the classification of the superordinal groups, orders and families of angiosperms by the APG II (2003), Takhtajan (1997) and Cronquist (1988) is presented. The linear sequence of the orders (45) and families (453) is that of the APG. The APG provided a new model of phylogenetic classification. The framework of Superordinal groups such as Magnoliids, Monocots. Cornmelinids, Eudicots, Rosids and Asterids is fully resolved. But many details for understanding the relationships between many of the basal clades of angiosperms, among major eudicot lineages, and many orders such as Malpighiales and Asterales remain to be resolved. Thus, all the accepted order and family names are listed in alphabetical order. Under the superordinal groups there are listed a number of families (32) without assignment to orders, as their ordinal positions are still unclear to the APG. For the present purpose 2 superordinal groups such as "Basal families" and "Prorosids" and 25 additional ordinal names are optionally adopted with quotation-marks/question mark, italics and parenthesis. Nevertheless seven ordinal positions remain unnamed. Monocots are placed between the Magnoliids and the Eudicots. The APG updated 19 orders with new consignment of families. They have emended (recircumscribed, expanded or restricted) 65 families. There are fifty five (55) square bracketing families below these updated 65 families with which they may be merged or relegated. The APG widely shifted 23 families and deleted about 46 popular families in favour of other broadly circumscribed families. Nineteen (19) obsolete families are reinserted along with a fresh list of 'taxa incertae sedis' of four families and 13 genera. The demise of Avicenniaceae and Flacourtiaceae, the restriction of Euphorbiaceae to the uniovutate subfamilies and the addition and alteration in Scrophulariaceae are noteworthy. The placement of Ebenaceae and Ericaceae in a larger clade Asterids (= sympetale) is a reversion to the earlier concept.

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