In the young of Selachians and certain Teleosts (e.
In Teleosts the plexus has become condensed to form a definite sympathetic trunk on each side, extending forwards into the head and communicating with the ganglia of certain of the cranial nerves.
In various Teleosts the scales are vestigial (eel); in others (as in most electric fishes) they have completely disappeared.
In a few Teleosts (Salmonidae, Muraenidae, Cobitis) the ovary is not a closed sac, its eggs being shed into the coelom as in other groups.
Certain deep-sea Teleosts possess remarkable telescopic eyes with a curious asymmetrical development of the retina.
In the Teleostomes the olfactory organ varies from a condition of great complexity in the Crossopterygians down to a condition of almost complete atrophy in certain Teleosts (Plectognathi).
In the great majority of Teleosts and in Lepidosteus the oviduct possesses no coelomic funnel, its walls being in structural continuity with the wall of the ovary.
In various Teleosts the swimbladder enters into intimate relations with the otocyst.
On this interpretation the condition characteristic of Teleosts would be due to the lips of the oviduct becoming fused with the ovarian wall, and the duct itself would be a Muellerian duct as elsewhere.
In various Teleosts the pectoral fins have acquired secondarily a leg-like function, being used for creeping or skipping over the mud (Periophthalmus; cf.
In the majority of the Teleosts the absence of spiral valves is coupled with a secondary elongation of the intestinal region, which in extreme cases (Loricariidae) may be accompanied by a secondary spiral coiling.
In Amia and in Teleosts a network of capillaries forming the so-called choroid gland surrounds the optic nerve just outside the retina.
In the Teleosts and in Polypterus there is no obvious connexion between testis and kidney, the wall of the testis being continuous with that of its duct, much as is the case with the ovary and its duct in the female.
In most but not all of the species the tail is distinctly and obviously heterocercal, the lack of symmetry of the tail in some Teleosts being confined to the bones and not evident without dissection.
Arapaima, Osteoglossum, and Clupeiform types) agreeing with typical physostome Teleosts in the skeleton, heart, etc.
Teleosts than between the former and the other orders of Ganoids, but it is equally true that they agree in other respects than in the brain and heart with the more generalized Ganoids.
In a general way the skeleton of all Teleosts corresponds with that of the striped bass (see Figs.
In the unsymmetrical teleosts or flounders, and soles, this condition no longer obtains.
But it is quite possible that among some of the generalized Teleosts at least traces of some of the characters now considered to be peculiar to the Ganoids may be discovered.
The transition from Ganoids to Teleosts is of much the same character as the transition from spiny-rayed to soft-rayed fishes, or that from fishes with a duct to the air-bladder to those without such duct.
In the Mesozoic seas these fishes were scarcely less varied and perhaps scarcely less abundant than the Teleosts in the seas of to-day.
Arthrodirans may have represented the dominant group in the Devonian period, as were the sharks in the Carboniferous, or as are the Teleosts in modern times.
The process of the development of the germ-layers inTeleosts appears as an abbreviated one, although in many of its details it is but imperfectly known.
In the sharks, dipnoans, crossopterygians, ganoids, and teleosts or bony fishes, jaws are developed as well as a variety of other bones around the mouth and throat.
It is equally evident, after a detailed comparison, that the single coracoid element of the Ganoids represents the three elements developed in the generalized Teleosts (Cyprinids, etc.
All these characters are found in the earlier types so far as is known, and all are more or less completely lost or altered in the teleosts or bony fishes.
The formation of the mesoderm in Teleosts is not definitely understood.
One of the important differences between the ganoids and the teleosts or true fishes is in the tail vertebrae.
So far as we know the Shad family is the first of ourteleosts or true fishes to appear, and these were quite abundant in the early part of the Triassic.
In the teleosts both lobes are nearly the same size.
In the teleosts the tail vertebrae ends a short distance in front of ends of the middle fin rays of the tail fin.
It is true that the pancreas in certain teleosts is now known to be present although concealed from observation in the liver or scattered in the form of small lobules between the layers of the mesentery (cf.
To the same physiological category belong the digestive diverticula of the intestinal canal, such as the pyloric appendices of the midgut found in many teleosts and ganoids (cf.
This close association of the hepatic duct with the pancreas is well seen in the arrangement of the concealed pancreas of some teleosts (cf.
A second modification of the intestinal canal, suggesting the same physiological interpretation as the ileo-colic caecum, is presented by the so-called pyloric caeca or appendices of many Teleosts and Ganoids already referred to (p.
On the other hand in the Ganoids and in many Teleosts longer or shorter finger-shaped diverticula of the midgut are found immediately beyond the pylorus in the region of the bile-duct.
On account of this concealed position of the gland it was formerly believed that the adult teleosts did not possess a pancreas.
In some Teleosts (Siluroidea, Labroidea, Cyprinodontia, Plectognathi and Leptobranchiates) the appendices are entirely wanting.
In certain adult teleosts the pancreas is surrounded by the liver (Fig.
In the Teleosts the liver arises quite late (in the trout about the 25th day) as a solid outgrowth from the intestinal canal close to the heart.
It is interesting to note that the modern teleosts in their embryological growth pass through the stages which characterized the maturity of their Devonian ancestors; their skeleton is cartilaginous and their tail fin vertebrated.
The teleostsare a highly specialized type, adapted most perfectly to their aquatic environment.
The third suborder of teleosts contains eellike fishes of the tropics; and the fourth contains the true eels and their relatives.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "teleosts" in a variety of sentences. We hope that you will now be able to make sentences using this word.
