166 ^ESTIVATION OF BOTRYLLOIDES GASCOI DELLA VALLE. 



EXPLANATION OF PLATE XL 



ABBREVIATIONS. 

 a. Ampulla. /3. Bud. y. Hole in the colony. 



1, 2, S, etc., indicate the same zooids in all the figures. 



PLATE XI. 



Figs. 1-9. Outline camera drawings of the living colony during rejuvenescence, showing some of the buds, zoords; 



and ampullae. The opaque parts of the colony are indicated by stippling. X 12. 

 Fig. 1. Outline of a living colony showing all the buds to be seen July 29; a indicates a characteristic group 



of ampullae that serves as a fixed point to measure from. 

 Fig. 2. The same colony as shown in Fig. 1, on July 30. The buds have moved farther away from a and have 



formed the first system. The buds marked /? in Fig. 1 have degenerated. 

 Figs. 3-9. A series of drawings at daily intervals, or less, of all the buds (except one) and the zooids in the 



rejuvenating colony, from the degeneration of the second to the formation of the third system. 

 Fig. 3: Aug. 15, 2 p.m. The more abundant stippling indicates the more opaque part of the colony. The two 



circles above are not buds, but mark the place where some zooids degenerated. 

 F g. 4. Aug. 16, 12 m. System 2 degenerating. 

 Fig. 5. Aug. 16, 6 p.m. Same as Fig. 4; small circles are buds. 

 Fig. 6. Aug. 17, 8.30 a.m. 

 Fig. 7. Aug. 18, 9 a.m. 



Fig. 8. Aug. 19, 10 a.m. There is a bud in another part of the colony, not included in this figure. 

 Fig. 9. Aug. 20, 9.30 a.m. The bud not included in the figures is degenerating. 

 Figs. 10-12. From sections through half of the colony, preserved on July 15; Davidoff's fluid; Benda's iron 



hsematoxylin. X 850. 

 Fig. 10. The smallest bud seen, situated in a blood-vessel. 

 Fig. 11 A typical bud, showing the varying thickness of the inner vesicle, and the connection of the outer 



vesicle with an ampulla. 

 Fig. 12. A bud with a small ampulla for an outer vesicle. 



