'PVLORIC GLAND" OF THE ASCIDIAN BOTRYLLUS. 43 



in contrast to the blood and to the sea water, the contents of the 

 lumes of the tubes and bulbs i- very bmxvn. There are two alter- 

 natives by which IM interpret tin--. t\\ . . experiments either these 

 stains act as indicator- or th< actually concentrated in the 



lumen of the organ brin- ted from the blood by the cells 



of the \\ all- of the tube- and ampul I.e. Beyond certain leucocytes 

 located in the neighborhood of tin \\hich -eem to collect 



tin- dye, the only other cell- that take up the ammonium car- 

 mi nate and indigo i a rm in are the vat ii"K-- in the inte-tinal cells. 



A cro . lion of the inte-tine ha- the -hape of a rectangle (Fig. 



17 . the end- of \\hich are made up of an epithelium of Hat cells 

 bearing cilia, \\hile the -ide- are thick and are compo-nl of iwo 

 ^orl- of i olumiiar cell-. ilialed and glandular I u. 14). The 

 Inland i ell- muler ordinary condition contain a cK-ar lit|iiid. It 

 is the vacuolea ot tin se -Jand < ill- \\ hich -lain -lightly in ammon- 

 ium carminati- and im ; rmin. The -ignilicance of this will 

 be ili-i USSed later on. 



Both Mul'^iiln and . 1 M ?/;</ \\eiv tn.ited \\ilh indigo carmin at 

 I'" mforl but llie p\ loric gland -hou.,1 no reaction to them. 



In .S7\'(7</, ho\\e\er. indigo carmin in concentrations as shown 



in the table ;^,i\e in e\ ei 'eri-tic reaction. The 



malerial in < |iie-t ion \\eie rather -mall .S'/vc/.: 20 ^> mm. The 

 large ones i e< |nii i-d too 1., epiacl- 



I- \|.i-iinn nt i . rater 4 d 



dip' r.uinin in 

 2 I"" C.C. do 



i" .!> 4 



I 



The animal- in experiment- I, J and ^ li\ed, in experiment 4 

 the\ died. 



\\lien the animal- \\ < ruined lar-e blue concretion- \\ere 



found in the ampulla- and duct- of the p\ loric gland 1 igs. 25 

 and 26). These concretions gave that portion l the inte-tine 

 Covered b\ tin- p\ loric -land a blue color. The writer con- 

 sider^ that the indigo carmin wa- excreted from the blood into 

 the canal- of the J md. 



