Decapods sentence example
In the seas, bony fish and crab-like decapods increased in numbers and variety, while pelecypods and gasteropods took the prominent place previously occupied by ammonites and belemnites, and, leaving behind such forms as Rudistes, Inoceramus, &c., they gradually developed in the direction of the modern regional groups.
The decapods and other zooplankton in the samples were dried and weighed.
Organs of this type are best known in the Euphausiidae among the Schizopoda, but a modified form is found in some of the lower Decapods.
A very curious function sometimes discharged by the antennules or antennae of Decapods is that of forming a respiratory siphon in sand-burrowing species.
The green gland and the structures associated with it in Decapods were at one time regarded as constituting an auditory apparatus.Advertisement
True Decapods are first met with in Mesozoic rocks, the first to appear being the Penaeidea, a primitive group comprising the Penaeidae and Sergestidae, which occur in the Jurassic and perhaps in the Trias.
In most Decapods the " stomach " or dilated portion of the fore-gut is divided into two chambers, a large anterior " cardiac " and a smaller posterior " pyloric."