English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

A description is given of the activity of the thyroid and of the pituitary gland during the development of the gonopodium in the viviparous Cyprinodonts Lebistes reticulatus (Peters), Xiphophorus helleri (Heckel) and Xiphophorus maculatus (Gunther). During this process the thyroid gland and the glandular lobe (lobus anterior and lobus intermedius) show a gradual increase in activity. This activity was in general most pronounced in Lebistes reticulatus (Peters) and weakest in Xiphophorus maculatus (Gunther). This increase in activity suggests that the developement of the gonopodium is probably regulated endocrinally. For the determination of the state of thyroid and pituitary activity use was made of the quotients d/n and D/n (Lever, 1948 and 1950; cf. Lever, Miltenburg and Van Oordt, 1949, and Stolk, 1951 c, 1956 g, 1957 b and 1958 b) and the quotients ch and cs (Stolk, 1954, 1955 a, 1956 a, 1956 c, 1956 d, 1956 e, 1956 f, 1957 a, 1958 a and 1958 b), respectively, and moreover of the nucleus size, the mitotic activity, the nucleus structure, the chondriome and the Golgi apparatus.

bijdragen tot de dierkunde

Activity of the Thyroid and the Pituitary Gland in the Viviparous Cyprinodonts Lebistes Reticulatus (Peters), Xiphophorus Helleri Heckel and Xiphophorus Maculatus Günther during the Development of the Gonopodium