|
|
|
|
|
O'Herne, L.. |
Foraminiferal collections from Java and Borneo stored in the Netherlands National Museum of Geology and Mineralogy in Leiden enables to study the range of variation in Lepidocyclina ferreroi and L. multilobata. Taken separately many features considered typical of L. multilobata and L. ferreroi are insufficient to identify the specimens. When typically developed both species are highly characteristic and easily distinguished. Transitional forms however cannot be classified with certainty. Possibly L. multilobata has evolved from L. ferreroi but too little is known about the ages of the two species, especially of L. multilobata. L. crucifera is probably a form of L. ferreroi with four rays distinguished by the development of more than one tubercle on each... |
Tipo: Article / Letter to the editor |
Palavras-chave: 38.20. |
Ano: 1976 |
URL: http://www.repository.naturalis.nl/record/317538 |
| |
|
|
O'Herne, L.. |
At least three of the forms described by Brady (1884) as Amphistegina lessonii show specimens with monocular as well as bilocular nucleoconches, probably representing the microspheric and macrospheric generations. Except for the shape of the embryonic apparatus both generations are identical or practically so. Assuming that dimorphism occurs in Amphistegina, the above suggests that several species should be distinguished in Brady's Amphistegina lessonii. The internal structure of A. lessonii is illustrated by photographs and schematic drawings. |
Tipo: Article / Letter to the editor |
Palavras-chave: 38.20. |
Ano: 1974 |
URL: http://www.repository.naturalis.nl/record/317469 |
| |
|
|
O'Herne, L.. |
Graphs, showing the relation of the primary chambers to the number of their secondary chamberlets, demonstrate that Tan's nepionic mutants are variable, even in the course of a short period. The evolutionary change of the nepionic mutants is consistent with the evolutionary change of Cycloclypeus as a whole. The number of secondary chamberlets of the first neanic chamber is considered a valuable characteristic for the identification of species. Reduction of the number of nepionic chambers in the course of time is thought to result from the occurrence of 'transitional nepionic variants'. |
Tipo: Article / Letter to the editor |
Palavras-chave: 38.20. |
Ano: 1972 |
URL: http://www.repository.naturalis.nl/record/317468 |
| |
|
|
|