SCIENTIFIC SUMMARY, 
211 
The Nest of the Gourami . — M. Carbonnier has studied and described the 
habits of several species of fishes belonging to the curious group of the 
Labyrinthici, the u Pharyngiens labyrinthiformes ” of Cuvier, so called 
from the singular structure of their pharyngeal bones, which constitute on 
each side a labyrinthic cavity for the reception of water, serving to moisten 
the gills when the fish is out of its native element. The Climbing Perch 
(Anabas scandens ) of India is perhaps the most generally known species of 
this group, but the most important one is the Gourami ( Osphromenus olfax ), 
an inhabitant of the fresh waters of China and India, which grows to a 
large size, and is highly esteemed for the excellence of its flesh. The 
history of its nidification, as told by M. Carbonnier, is very curious. As 
in the case of most if not all nest-building fishes, the labour falls to the lot of 
the male. M. Carbonnier placed his gouramis in an aquarium containing 
about 48 gallons of water, which he kept at a temperature of 77° Fahr. In 
a few days the bodies of the males displayed brilliant colours, and they 
began to pursue each other, and struggled furiously for the regards of the 
females. Having selected the finest male, M. Carbonnier left him in the 
aquariumjwith a female into whose good graces he seemed particularly anxious 
to insinuate himself. He soon commenced in one of the corners of the 
aquarium the formation of a frothy nest, which in a few hours was 6 or 
7 in. in diameter and 4 or 5 in. high. He then rose to the surface of the 
water, and drawing in a supply of air, gradually emitted it in the form of 
bubbles, englobed by the mucous secretion of the mouth ; these bubbles 
he collected and carried into his nest. The nest being completed, the male 
watched by it patiently, and whenever the female approached he displayed 
his brilliant colours, until at last he seized her and caused her to perform a 
first spawning, and these operations were repeated until all the eggs were 
laid. In order to raise these into the floating nest the male now adopted a 
singular device. Rising to the surface, he took in an abundant supply of air, 
and then, descending, he placed himself well below the eggs, and suddenly, 
by a violent contraction of the muscles of the mouth and pharynx, drove 
the air contained in them out through the branchial apertures, from which 
it issued so divided by passing among the lamellse and fringes of the gills, 
that it formed two jets of a regular gaseous dust which enveloped the eggs 
and carried them up towards the surface. After the operation the male 
gourami himself looked as if he had been sprinkled with thousands of 
minute pearls. The number of eggs produced was estimated by M. Carbon- 
nier at between two and three thousand, but only about six hundred of 
them hatched. For three days the young fishes resemble globular tadpoles, 
but within six days after hatching their development is completed. Then 
commence the paternal troubles of the male, for the young fishes, with the 
conceit and heedlessness natural to their time of life, immediately begin 
escaping from the shelter of their nest. The male, however, pursues them 
and drives them back by means of jets of air-bubbles, and it is not until 
about ten days after hatching that they are left to wander at their own 
will and pleasure. M. Carbonnier states that he has 520 young gouramis 
which were hatched in his aquarium in July last, and which at the begin- 
ning of December were from 1^ to in. long. He seems to hint at the 
possibility of acclimatizing the fish in Europe, and remarks that, among 
