Zobrazeno 1 - 4
of 4
pro vyhledávání: '"N. H. Kirk"'
Autor:
N. H. Kirk, D. E. B. Bates
Publikováno v:
Bulletin of the Geological Society of Denmark. 35:85-102
Spinose and laciniate Ordovician graptoloids are briefly described and an attempt is made to explain the formation and anastomosis of their spines by secretion by cells within the mesenchyme of an extrathecal mantle. It is suggested that in Pipiograp
Autor:
N. H. Kirk
Publikováno v:
Geological Magazine. 117:277-284
SummaryRecent ideas on evolution in the graptolites have been based upon an assumption either of passive flotation and passive feeding, or of active and co-ordinated ciliary feeding resulting in automobility. These ideas are compared and a possible e
Autor:
N. H. Kirk, D. E. B. Bates
Publikováno v:
Geological Society, London, Special Publications. 20:221-236
Autor:
N. H. Kirk
Publikováno v:
Geological Magazine. 112:322-324