in diameter and are only four in number, they being proportionally the largest Teleostome eggs known. Thus they may be moderately large and numerous (zoo to 200) in Tilapia nilotica and galilaea, larger and only about 30 in number in Paratilapia multicolor, while in Tropheus moorii, a fish measuring only i io mm., the eggs filling the mouth and pharynx measure 4 mm. The relative size and number of the eggs thus taken charge of vary very much according to the species. It therefore remains unproven whether in any of the African Cichlidae the buccal "incubation," as it has been called by Pellegrin, devolves on the male the instances previously adduced being unsupported by the only trustworthy evidence - an examination of the genital glands. Schoeller on Paratilapia multicolor, have led to the same result. Further observations by Pellegrin on Tilapia galilaea and Pelmatochromis lateralis, by E. Pellegrin has acertained the female sex of a specimen with eggs in the mouth presented to the Paris museum by Lortet as his Chromis paterfamilias (= Tilapia simonis). Boulenger has since had an opportunity to examine the latter specimen and found it to be a female, as in all other nursing individuals from various parts of Africa, previously observed by himself whilst J. Gunther had also ascribed the same sex to a fish from Natal, Chromis philander, observed by N. Lortet had described a fish from Lake Tiberias in which he believed he had observed the male take up the eggs after their deposition and retain them in his mouth and pharynx long after eclosion, in fact until the young are able to shift for themselves, and this fish he named Chromis paterfamilias. We are now acquainted with a large number of species in which this extraordinary habit has been observed, the number having lately been greatly increased by the collections made in Lakes Tanganyika and Victoria.
#Tilapia galilaea size series
This may still be true of some of the American species, but a long series of recent observations have shown that this most efficacious parental care devolves invariably on the female in the African and Syrian species. It was formerly believed that the male takes charge of the eggs, and later the young, by sheltering them in the mouth and pharynx. These fish are further remarkable for their nursing habits. They were formerly known under the inappropriate name of Chromides. About 180 species are known from Africa (with Syria and Madagascar), 1 5 o from America, and 3 from India and Ceylon.
It has recently assumed special importance through the large number of genera and species, many of them showing extraordinary modifications of the dentition, which have been discovered in tropical Africa, especially in the great lakes Victoria, Tanganyika and Nyasa. CICHLID ( Cichlidae), a family of Acanthopterygian fishes, related to the perches and wrasses, and confined to the fresh and brackish waters of Central and South America, Africa, Syria, and India and Ceylon.
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