So too is the allied Plagiochaeta with numerous setae on each segment but with the alternating and single nephridial pores of Maoridrilus.
A pair of genital apertures, connected by genital ducts with the paired gonads, are found right and left near the nephridial pores, except in a few cases where the genital duct joins that of the renal organ (Spondylus).
The genital duct opens by a pore into the urino-genital groove of the oyster (the same arrangement being repeated on each side of the body) close to but distinct from the aperture of the nephridial canal.
Whitman the entire nephridial system (in the leech Clepsine) is formed by the differentiation of a continuous epiblastic band on each side.
The nephridia of the Polychaeta have been generally dealt with above in considering the nephridial system of the Chaetopoda as a whole.
Here also the genital funnels have either replaced or been formed out of nephridial funnels.
Burger) in coelomic spaces close to nephridial funnels, which have, however, no relation to the gonad ducts.
It is further noticeable that in Rhynchelmis the covering of vesicular cells which clothes the drain-pipe cells of the adult nephridium is cut off from the nephridial cells themselves and is not a peritoneal layer surrounding the nephridium.
If the genital funnels are not wholly or partly formed out of the nephridial funnels they have replaced them.
At the least there is no doubt that the genital funnels are developed precisely where the nephridial funnels formerly existed.
In all the figures the nephridial pores are indicated by dots and the setae by strokes.
Here again the nephridial funnel seems to have been converted into or certainly replaced by a secondarily developed funnel.
Diagram to show the relations of the four nephridial sacs, the viscero-pericardial sac, and the heart and large vessels in Nautilus (drawn by A.
Reno-pericardial orifice placing the left renal sac or nephridium in communication with the viscero-pericardial sac, the course of which below the nephridial sac is indicated by dotted lines.
Diagram of the nephridial sacs, and the veins which run through them, in Sepia officinalis (after Vigelius).
The nephridial sacs are supposed to have their upper walls removed.
If, as is possible, it is homologous with the Ascidian hypophysial gland, then it is confirmatory evidence that this latter is said by Julin to be an altered nephridial organ.
Each solenocyte consists of a cell-body and nucleus situated at the distal free extremity of a delicate tube; the proximal end of the tube pierces the wall of the nephridial canal and opens into its lumen.
We should, therefore, expect to find secretory nerves to nephridial organs, though possibly not to coelomostomes.
The nephridial papillae occupy the ordinary position; they are small and unusually short.
A characteristic feature is the elongate form of the nephridial papillae, these in the type as preserved being mostly near three times as long as thick at the middle.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "nephridial" in a variety of sentences. We hope that you will now be able to make sentences using this word.
