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Show 1895.] HYDEACHN1D POUND IN COENWALL. 191 complicated than, those described by Schaub and partially described by Croneberg. In the first place, instead of their blind distal end being attached near the mouth it is attached to the side of the body about halfway back and opposite the genital organs: the gland is not in any way bent into a loop ; its direction is forward for its whole length, but it is greatly and irregularly corrugated and twisted for about two-thirds of its course; in this part it has an average diameter of about *02 mm., is a fleshy organ composed of largish secreting-cells, and has a very small lumen. The gland suddenly narrows at the end of this portion, loses its twisted and corrugated form, and becomes straight; it is still somewhat fleshy in appearance, and has a diameter somewhat less than half the diameter of the corrugated part; its largest diameter is in the centre, and it narrows at both ends to about half the diameter of the centre. This tract of the gland may be considered as the duct; it is usually filled with small round granules (secreted matter), very similar to that spoken of by Schaub in the distal portion of his tubular gland and by Croneberg in the same portion in Trombidium ; except that, in consequence of the larger diameter of the organ now being described, the granules do not follow each other in single file as they do in Schaub's drawing. After this portion the duct suddenly expands again and becomes a large transparent ovate bladder, with thin, apparently structureless walls (fig. 16, sb.). The diameter of this bladder in its widest part is larger than that of any other portion of the whole duct; at its anterior end it narrows sharply, and there is a very short tubular part which turns suddenly downward and backward to join the main general duct. This description is not taken from a single specimen, all the numerous specimens which I have dissected have been alike. The only record at all resembling this bladder is Pagenstecher's respecting Trombidium. It now remains to describe the precise manner in which the various glands above described communicate with the common duct (main general duct). There is one of these common ducts (D.) on each side of the body, and all the three salivary glands on that side communicate with it; it is of an almost uniform diameter until near its posterior end, wiiere it enlarges somewhat suddenly both in a lateral and in a dorso-ventral direction; the small anterior end or prolongation of the bladder of the tubular gland enters the common duct in the middle line of the upperside of this enlargement, and the two ducts from the reniform gland enter the lateral edges of its upper part, one on each side. The two ducts from the quadrate salivary gland enter the tubular part of the common duct close together some distance nearer to the mouth than the entrance of the ducts from the reniform glands. At the posterior end of the lower part of the enlargement of the common duct, another tube (du.), which at its starting point is of nearly as large diameter as the tubular portion of the common duct but rapidly diminishes and becomes very fine, runs at first backward and then almost perpendicularly downward. I have not been able |