In the dimorphic stag’s hom fem, Platycerium coronarium (Koenig ex Mueller) Desv., photosynthetic characters and chlorophyll (Chl) contents were deteiinined in both nést and pendulous fronds at different stages of ontogeny and at different positions along the longest length of each frond. Area-specific radiant energy- saturated net photosynthetic (P^) and dark respiration rates, dry mass-specific Chl content and quantum yield increased during frond development and decreased when senescence set in. Radiant energy-saturated and dry-mass specific Chl content were greatest in the youngest tissues of each frond. In addition to the functions ascribed to the nést (water and nutrient collection) and pendulous (reproduction) fronds, the results indicate the important roles of both frond types in providing Chemical energy to the growth and survival of the plant.
The family Rhopalothylacidae (Cestoda: Trypanorhyncha) is reviewed. The type species, Rhopalothylax gymnorhynchoides Guiart, 1935, is redescribed from the type specimens and belongs within the genus Pintneriella Yamaguti, 1934, previously described only from the plerocercus. Rhopalothylax therefore becomes a junior synonym of Pintneriella. The adult of Pintneriella musculicola Yamaguti, 1934 is described for the first time, from the shark Carcharias taurus Rafinesque from Australia. Pintneriella is characterised by two bothridia, a typical heteroacanthous armature, a unique, bipartite external seminal vesicle and a uterus deviated porally, terminating at a uterine pore. It belongs within the Heteracanthoidea but is distinguishable both from the Eutetrarhynchidae and the Gilquiniidae, the two families which it most closely resembles. Cladistic analyses align Pintneriella within the clade containing the families Gilquiniidae, Gymnorhynchidae and Molicolidae rather than with the Eutetrarhynchidae. The family Rhopalothylacidae is therefore retained provisionally to accommodate Pintneriella within the Heteracanthoidea. The second genus of the Rhopalothylacidae, Clujia Guiart, 1935, is unrecognisable from its description and cannot be redescribed from its holotype. It is therefore considered a genus inquirendum.