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In all the other animals the central nervous system has been developed in a totally different way from the upper pharyngeal ganglion; in the Articulates, especially, a pharyngeal ring, with ventral marrow, has been added. The Molluscs also have a pharyngeal ring, but it is not found in the Vertebrates.
It thus has two pectoral, one dorsal, and one ventral fin, properly speaking; but the greater part of the body is surrounded by some cartilaginous substance which it probably uses as a fin; under the line b c there is a curved portion of this matter, and above and attached to the fish is a line of round white silvery scales, about ten in number.
When the larva is floating on the liquid honey, it is as it were steadied by the excessive development of the ventral surface immersed in the honey, which enables it to acquire an equilibrium that is of the greatest importance to its welfare.
In thus writing of reversed and normal it must be understood that the former word does not mean merely turned over, for in that case right side of the body would be joined to the left side of the head, and the dorsal fin would be next to the ventral side of the head, which is not the case.
We know that the American artist and naturalist Thayer has shown that the lighter colour of the ventral side of birds and other animals aids greatly in reducing their visibility in their natural surroundings, the diminution in coloration compensating for the diminution in the amount of light falling on the lower side, so that the upper and lower sides reflect approximately the same amount of light, and contrast, which would be otherwise conspicuous, is avoided.
The species figured in the accompanying drawing is the Hydrophis subloevis of Gray; or Hydrus cyanocinctus of Boie. The specimen from which the drawing is taken, was obtained by Dr. Templeton at Colombo. Scales nearly smooth; ventral plates broad, six-sided, smooth, some divided into two, by a slight central groove.
At the moment when the Osmia disgorges her honey and especially at the moment when, with her hind-tarsi, she rubs the pollen-dust from her ventral brush, she needs a narrow aperture, just big enough to allow of her passage. I imagine that, in a straitened gallery, the rubbing of her whole body against the sides gives the harvester a support for her brushing-work.
Until recently it was regarded as a general rule that, by the partial segmentation of the vitellus a germinal disc was formed, and in this, corresponding to the ventral surface of the embryo, a primitive band. According to Mr.
A book of Chinese paintings showing the Golden Carp in its varieties represents some as short and stout, others long and slender, some with the ventral side swollen, others hunch-backed, some with the mouth greatly enlarged, while in others the caudal fin, which in the normal condition of the Species is placed vertically at the end of the tail and is forked like those of other Fishes, has become crested and arched, or is double, or crooked, or has swerved in some other way from its original pattern.
The former belonged to the Siluridae, and had four fleshy appendages on the lower lip, and two on the upper; dorsal fin 1 spine 6 rays, and an adipose fin, pectoral 1 spine 8 rays; ventral 6 rays; anal 17 rays; caudal 17-18 rays; velvety teeth in the upper and lower jaws, and in the palatal bones.
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