134 E. R. HOSKINS AND M. M. HOSKINS 



probably indicate an abnormal attempt at leucocytosis by 

 amitotic division. 



Other masses of lymphoid tissue were not examined, but they 

 probably are phagocytic to dye granules. 



5. Spiral valve and postvalvular intestine 



Denis ('13) mentions the possibility of an excretory function 

 possessed by the intestine of dogfish. Several of the solutions 

 and dyes which we injected were found later in the spiral valve. 

 However, these entered the intestine partly if not entirely in 

 the bile. With Weed's solution Prussian blue was not deposited 

 in the epithehmn nor were any granules of injected dye found in 

 it. Potassium iodide was obtained in the spiral valve after ni- 

 jection, but this will go through almost any gland and is not a 

 specific test. Indigo-cannine did not stain the epithelium, nor 

 could it be detected in the contents of the spiral valve. Experi- 

 ments in which solutions of various kinds, including dyes, are 

 injected, should be performed with dogfish in which bile is pre- 

 vented from entering the intestine. We hope to do this at a 

 later date. The toxins injected caused severe injury to the 

 spiral valve whether the bile was permitted to enter the intes- 

 tine or not. In every case there was severe congestion and 

 destruction of a considerable amount of the epithelium. The 

 capillaries in the mucosa ruptured producing hemorrhage into 

 the intestine. These vessels were injured probably more that 

 those in any other organ, although there was some vascular 

 injury in the kidney. The spiral- valve contents were tested for 

 the toxins that had been injected, but even with small amounts 

 of blood and bile present the tests were not sufficient to deter- 

 mine the presence of the toxins. Probably more delicate tests 

 would be successful. Our not finding some of the injected solu- 

 tions in the spiral-valve contents also was due possibly to tests 

 not sufficiently delicate. While the injury of the spiral valve by 

 excretory toxins does not absolutely prove that this organ has 

 normally an excretory function, it tends to support the theory. 

 The fact that intestine posterior to the spiral valve was not 

 injured at all by the injected poisons adds evidence in favor of 

 this theory. 



