392 Miscellaneous, 



On the Lymphatic Vessels in the Tail of the Toung of Batrachia. 



By C. Langer. 



Successful injections of this system of vessels facilitated the de- 

 tection of many uninjected vessels, which could be traced from the 

 ends of the injected portions of the tubes for a long distance in the 

 tissue of the border of the tail. They not only permitted the ar- 

 rangement of the whole system, but also the structure, connexion, 

 and termination of the individual vessels to be investigated. 



The author found that they have sharply marked, even outlines, 

 without any indentations. Their appearance, as regards the consti- 

 tution of the walls and the form of the nuclei, was hardly different 

 from that of the fine blood-vessels. The limitation of the capillary 

 lymphatic ducts by proper walls is easily ascertained in this object. 



The capillary lymphatic vessels form a network, which in the 

 smaller tadpoles, and in the fine border of the tail in larger ones, is 

 diffused only in a single layer, but is overlaid on both sides with the 

 network of blood-capillaries. 



At the margin of the vascular region there are capillary lym- 

 phatic loops, of which some are remarkably narrowed ; but even in 

 the interior of the border, thread-like anastomosing branches are also 

 met with so much narrowed that their complete impermeability seems 

 a matter of course. This supposition is rendered still more probable 

 by the discovery of similar portions attached to injected ducts. In 

 this case they had also in part become coloured, but were only per- 

 meated as far as to the narrow part, usually furnished with a nucleus, 

 where the coloration was limited to the form of a pointed narrow stripe. 



Caecal terminations of the lymphatic tubules also occur; these 

 issue broadly from the wall of a capillary, and usually terminate 

 quickly in a point, after producing a nucleus. It is possible that 

 some of these extremities may be only apparently constructed in 

 this manner, and really represent only one arm of a very narrow loop, 

 the continuity of which cannot be traced ; but appended portions 

 which run out into a fine point, free on all sides, can hardly be re- 

 garded as anything but true caecal terminations of lateral ramifications. 



The signification of these, as also of the very narrow thread-like 

 loops, must be genetic. In favour of this view is their similarity 

 to the corresponding forms of the blood- capillaries, which are 

 regarded and described as tubules in course of development. We 

 must, however, in the author's opinion, know precisely what influ- 

 ence contractility and the treatment of the object may have upon 

 the form of the finest vascular tubes, before we can with certainty 

 regard all these vascular appendages as transition forms of new 

 ducts. — Anzeige der AJcad. der Wiss. in Wien, July 23, 1868. 



Deep-Sea Dredging off Spitzhergen. 

 The Naturalists of the fourth Swedish Expedition to Spitzbergen 

 have just returned to Stockholm, among them Smitt and Malmgren, 

 the zoologists. Their collections are very considerable ; they have 

 brought up a good number of specimens from great depths, even 

 from more than 2000 fathoms. — Extract from a Letter from Prof. 

 Loven, received Oct. 2Qf 1868. 



