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BULLETIN 104, UNITED STATES NATIONAL MUSEUM 



spores (?)" which were then noted and have since been referred to 

 by various authors. These had small bodies at one side which took 

 stain more freely than the general mass. 



In the tow-nets in the work at the Tortugas I frequently took 

 Tretomphalus bulloides at the surface, especially in the open waters 

 off Loggerhead Key. Some of these had the "float-chamber" con- 

 taining a large air (?) bubble about half the diameter of the test, 

 Murray also noted this in his fresh material. In these pelagic 

 specimens there were often swarms of what were apparently zoo- 

 spores, capable of rapid movement, but showing no fiagellae or cilia, 

 so far as could be observed. It was suggested by Earland that these 

 might be discharged and on rupture of the "balloon-chamber" the 

 upper rotaliform portion might settle down to the bottom again and 

 live on as Discorbis or as Cymbalopora poeyi. My own observations 

 would tend to disprove this, for in all the specimens observed no 

 protoplasmic mass was left in the rotaliform portion, this also being 

 filled with zoospores, as was shown by crushing this part when none 

 were observed in the "float-chamber." On crushing such specimens, 

 numbers of zoospores came from the smaller chambers of the rotali- 

 form portion, but no undifferentiated protoplasm. Murray has al- 

 ready noted that none of his pelagic specimens contained the ordinary 

 form of protoplasm seen in the other foraminifera. These zoospores 

 are so minute (0.001 to 0.0015 mm.) that they could easily pass 

 through the pores of the spherical "balloon-chamber" and to it 

 from any part of the rotaliform portion through the apertures of the 

 early chambers. 



In connection with this, another very interesting fact was noted in 

 regard to the coloration of the initial portion of the test. It has 

 been assumed by most writers that the color of the test in certain of 

 the Rotaliidae, for example in Discorbis, was due to the contained 

 protoplasm. I had supposed that the specimens with deep color 

 were specimens in the living condition when taken. Heron-Allen 

 makes a similar note** in speaking of Tretomphalus bulloides as follows : 



"The color varies from pure white to a deep brown, owing to the 

 contained protoplasm, which is frequently as dark as in Discorbina 

 mediterranensis (d'Orbigny) and therefore of that group." 



Tretomphalus bulloides — Material examined 



"Philos. Trans, vol., 26, 1915, p. 257, footnote, p. 257. 



