Sumbionts in the female tsetse fly Glossina morsitans morsitans.

A rickettsia-like symbiont, located in the ovaries of G. m. morsitans is maternally transmitted to the offspring via the egg. It is suggested that they may be essential for normal ovarian development.

Micro-organisms in the midgut of tsetse fly larvae.

Two types of micro-organisms were found in the midgut of Glossina morsitans larvae, a large Gram-negative bacterial rod and a small Gram-negative rickettsia-like micro-organism, although the occurrence of the rickettsial type is restricted. The location of these micro-organisms in a small area of the proventriculus of all three larval instars is discussed. The large micro-organisms resemble milk-gland bacteria, and further evidence is presented in support of a milk transmission hypothesis for these micro-organisms.

Cytogenetical aspects of morsitans tsetse flies with particular reference to Glossina pallidipes (Diptera, Glossinidae).

The basic diploid chromosome of Glossina pallidipes is 2n = 6 and includes a pair of large sub-metacentric autosomes (L1), a shorter pair of metacentric autosomes (L2), and an X and Y which constitute a heteromorphic pair. The male meiotic sequence, although similar to that of other tsetse species, is characterized by asynapsis between X and Y chromosomes, and only tenuous association between the autosomes. Giemsa C-banding characteristics are described for the chromosomes of five species/sub-species and by means of this technique a whole range of hitherto unsuspected polymorphisms have been discovered. Polytene chromosome maps of G. pallidipes have been prepared and a description of all principal cytological markers is provided. A detailed comparison between these chromosomes and those of G. austeni has been conducted, and the conclusion is that although they must share a common ancestor, extensive band differences and structural change have occurred during phylogeny.