Pinna sentence example
- The Cyas type of frond, except as regards the presence of a midrib in each pinna, characterizes the cycads generally, except Bowenia and Stangeria.
- Such eyes on the mantle-edge are found in Pecten, Spondylus, Lima, Pinna, Pectunculus, Modiola, Cardium, Tellina, Mactra, Venus, Solen, Pholas and Galeomma.
- The sporangia arise simultaneously in the sorus, which is borne on the under surface of the ordinary pinna; in those species with large sporangia the latter form a single circle, in others sporangia may also arise from the central part of the receptacle.
- The development of the sporocarp shows that it corresponds to a pinna, although when mature it may appear to occupy a ventral position in relation to the vegetative portion of the leaf.
- Its nearest allies are Pinna among living forms, Eligmus among fossils.Advertisement
- B, Section of the rachis bearing a single pinna.