Volume 77, Issue 2
February 1973, pages 41-91
pp 41-55 February 1973
A resume on the morphological types of sclereids has been given under various typological heads with example drawn from the published literature to enhance their utility as distinct types in detailed description of sclereids. Depending on the constancy of the body shape the sclereids are classified into two main subdivisions: Monomorphic and Polymorphic. With some reservation, within the scope of the two subdivisions many types are recognised. It is emphasised that each type is a descriptive unit recognised for purpose of cogency in understanding.
pp 56-63 February 1973
Balanus amphitrite amphitrite D. is a common ship-fouling species encountered in many waters of the world. The larval metamorphosis of this species together with otherTetraclitid andChthamalid barnacles was examined under controlled laboratory conditions with a view to describing appropriately each of its six nauplii and cyprid stage. The naupliar characters such as setation of antennule, carapace sculpture, abdominal bulb and caudal process have been critically examined and their importance as the characters of diagnostic value has been discussed. The present study, carried out as it is on the live organisms, has helped to improve the descriptions of the larvae and has thus ensured their reliable identification in the plankton samples.
pp 64-77 February 1973
Embryogeny, histogenesis, shoot and root apical meristems, seedling, nodal and floral anatomy and the anatomy of the mature root, stem and leaf ofTecoma stans were studied. During histogenesis the radicular apex is the first to become distinct in the heart-shaped embryo, the epicotyl apex becoming organised later. The radicle has three tiers of initials one each for the stele, cortex and the third for the rhizodermis and root cap. This continues unchanged in the root. The shoot apex shows four cytohistological zones with two to three tunica layers. The node has unilacunar three-trace condition. The floral anatomy is simple and the members of each whorl develop antero-posteriorly. In the hypocotyl of the seedling the xylem and phloem do not split, the xylem groups rotating through 180°. The mature stem, root and leaf show normal structures.
pp 78-91 February 1973