Volume 25, Issue 5
May 1947, pages 95-162
pp 95-104 May 1947
The interesting forms described in this paper under the new generic nameBeaniopsis were found at Onthea in the Rajmahal Hills. Most of the specimens show well preserved female cones with distant sporophylls attached alternately to the cone axis by means of slender stalks. The stalk of the sporophyll is straight and like the cone axis its surface is longitudinally wrinkled. The distal end of each stalk is spoon shaped and bears two seeds on its upper surface. The exact mode of attachment of the seeds is not quite clear and must remain unsettled till better preserved material is found. Usually the seeds are placed in such a manner that the median lines marking the principal planes of the two seeds lie in continuation with each other and in the same plane as the long axis of the sporophyll stalk. The seeds are somewhat almond shaped with the base rounded and cordate, and the micropylar end is elongated and flattened. The micropylar ends of the seeds in a pair diverge from each other at a wide angle.
The genus is evidently a gymnosperm and the only groups to which a relationship can be suggested, with the present data in hand, are the Cycadales and less probably the Ginkgoales.
pp 105-118 May 1947
pp 119-125 May 1947
The forms described under the nameOntheostrobus sessilis come, as the name indicates, from Onthea. Most of the specimens show well preserved elongated receptacles bearing throughout their length numerous crowded seeds. The seeds are sessile and placed in shallow cupules which in turn are seated on cushions, the cushions being sessile on the receptacle. The receptacles from which the seeds have fallen off, show the exposed surfaces of the cushions slightly hollowed out. A small pit in the centre of this hollow marks the position of the vascular supply of the seeds. The detached seeds, usually found crowded together in their original groupings, show an elliptical scar at their chalazal end; this marks the area of attachment of the seeds with the receptacle. It is a noteworthy feature that not a single seed shows its micropylar end.
pp 126-154 May 1947
pp 155-162 May 1947
Aphrophora alni andA. Salicis each have one bacterium in symbiosis. In smears they are specifically different.A. salide. has a long bacillus ;A. alni, a short and delicate bacterium. These germs produce the pigments of their host insects, the symbiote ofA. Salicis an ochre yellow pigment, like the colour of the insect, that ofA. alni red-brown which is the colour of this species. Morphological and physiological tests have shown that the isolation of the symbiotes has been correct.
Sulc and Buchner have illustrated mysterious yeasts or fungi in symbiosis with these insects. These supposed germs are placed in a new genus, Cicadomyces. Details are given to show how they do not represent living entities. Even the authors themselves have subsequently discarded their earlier nomenclature and have designated these bodies simply as symbiotes, feeling themselves doubtful regarding the real nature of the objects they have illustrated. These are best interpreted as protoplasmic debris or pathological products without any nucleus, but merely with chromatinous residues, without any membrane to resist disintegration and digestion and above all incapable of being cultivated and indicating any evidence with regard to their function. These Cicadomyces show a great contrast to real yeast-like symbiotes which have been also illustrated for comparison.