Volume 77, Issue 1
January 1973, pages 1-40
pp 1-4 January 1973
This communication is a systematic account of species ofLacellinopsis collected and studied by the author. Observations [on morphology of setae and conidiophores have been presented. For ease of identification a key to known species is provided and further, their substrates and distribution is indicated.
pp 5-18 January 1973
Tricarpellary, syncarpous, unilocular ovary bears horizontal, bitegmic, crassinucellate and antropous ovules on three parietal placentae. Micropyle iszig-zag formed by both the integuments. The embryo sac is of Polygonum type and the pollen tube is persistent. The development of endosperm is nuclear and at maturity it becomes ruminate. The mature embryo is spatulate with two thin cotyledons and a short stubby hypocotyledonary region.
The outer integument is 4-layered inTacsonia and 3-layered inPassiflora but the inner is 3-layered in both. Seeds are covered with a succulent coloured aril which originates as a small outgrowth round the funiculus at the organised embryo sac stage. The seed coat is formed by both the integuments and is 7- or 8-layered inT. mollissima and 6-layered inP. caerulea andP. edulis. It comprises 6 zones of which the seed epidermis, radially elongated inner epidermis of the outer integument, the main sclerotic layer formed by outer epidermis of the inner integument are most conspicuous. The sclerotic layer consists of macrosclereids of various sizes and together with inner epidermis of the outer integument forms the ingrowths which make the endosperm ruminate.
pp 19-24 January 1973
The embryology ofOldenlandia umbellata Linn. has been investigated. Floral parts arise in acropetalous succession. A transection of an young anther shows a group of microscope mother cells followed by a layer of tapetum, a middle layer, an endothecium and an epidermis. The uninucleate tapetum is of the glandular type. Microspore tetrads are tetrahedral and isobilateral. The pollen grain is binucleate at the time of anther dehiscence and the endothecium fibrillar. A hypodermal archesporial cell directly functions as the megaspore mother cell. Embryo sac development follows the Polygonum type. Fertilisation is porogamous. Endosperm is free nuclear and embryogeny conforms to the solanad type.
pp 25-30 January 1973
pp 31-40 January 1973
The minute anatomy of the heart ofMabuya dissimilis has been described. The sinu-atrial aperture is devoid of the sinu-atrial valves. The posterior parts of the right and the left auricles are incorporated into the lumen of the ventricle as the atrium dextrum intraventriculare and atrium sinistrum intraventriculare respectively. The single auriculoventricular aperture is guarded by a single atrio-ventricular valve attached to the interatrial septum. Such constituents of the cardiac conducting system as the sinu-atrial plug and the atrio-ventricular plug do not, however, occur.