33i 



PATTERN OF BUDDING 



(i) Reduced group. In cormidia III-VII prominent gastrozooids are found at the oral end of the 

 cormidia, associated each with a characteristic, but atypical gonodendron (PI. XII, fig. 4). In 

 cormidia I and II on the other hand, each equally noticeable gastrozooid is linked both with a 

 gonodendron and with a tentacle (PI. XIII, figs. 3, 4), and lies on the aboral side of the tentacle. Thus 

 in cormidia I and II the reduced group is missing and the first one is tripartite like all the other com- 

 ponents of the cormidia (Text-fig. 13), whereas in cormidia III-VII the tripartite pattern of the first 



TENTACLES 1 1 GASTROZOOIDS PHHimi 



GONODENDRA 



3 



Text-fig. 13. Physalia physalis. Base of cormidium II (main zone) of a right-handed specimen, float-length 5 cm., from 

 St. 403, to show the tripartite nature of the first three groups. In cormidium II, all the groups including group 1 are tri- 

 partite. xii-5. 



group has been lost by the non-development of its tentacle. This pattern can generally be recognized 

 even in old specimens when viewing them from the windward side. All seven cormidia open separ- 

 ately into the pericystic space. Both the gastrozooid and the gonodendron of the first groups 

 (group 1) of cormidia III-VII appear to retain separate openings into the common atrium, or enlarged 

 and subdivided base of each cormidium (Text-fig. 12B). But if early stages of their development are 

 examined (Text-fig. 14 a) it can be seen that the gonodendron is budded from the base of the gastro- 

 zooid as usual. It is only because of the subsequent broadening of its base and incorporation into the 



