48 W. G. RIDEWOOD. 
axes only) is considerably longer* than wide (text-fig. 9, A, p. 27), and when 
four pairs of plumes are recognisable the same relation holds (text-fig. 9, B). In 
the adult, however, the antero-posterior diameter is only slightly greater than the 
maximum width (text-fig. 9, C). In C. dodecalophus the width is a little greater 
than the antero-posterior diameter (text-fig. 17, F, p. 54). In buds of C. nigrescens 
the width of the hinder lobe is less than that of the front lobe, but in adults it 
may be wider or narrower than the front lobe, or equal to it in width. The 
distance from the centre of the red line to the anterior edge of the shield is in 
young buds about twice the distance from the red line to the posterior edge. In 
adults the proportion is 24 times or 23. 
The stalks of buds of medium and large size are found in various degrees of 
contraction and extension, and even the same stalk may in one place be thin and 
smooth, and in another stout and transversely wrinkled. The stalks are so exten- 
sible in half-grown buds that these buds may be found entangled among the 
plumes of the parent individual, or may even project beyond. The stalks of such 
buds are of course greatly attenuated. 
Before severing its connection with the parent stolon, a large bud usually 
develops, at the side of the extremity of its stalk, a bud of its own, so that if the 
parting occurs at the extremity of the stalk (which is not always the case), the 
stalk has now to be regarded as the stolon of the liberated bud, with the first of 
its series of buds already present. 
The bases of the bud-stalks of an individual with several buds are disposed 
more or less in a circle around the hemispherical termination of the stolon, or 
slightly to one side of it. The order of sequence of the buds is not easy to trace, 
but it is not unusual to find small buds alternating with large buds around the 
circle. Figs. 69-75, plate 7, show the appearance of the end of the parent stolon 
after the stalks of the larger buds have been unravelled, and cut close to their 
origins. 
A feature of especial interest, as pointing to the possibility of the recognition 
in the stolon system of Cephalodiscus of such a system of branching as occurs in 
Rhabdopleura, is the occurrence—rare, it is true—among the buds at the end of 
the parent stolon of a sausage-shaped piece which at its free end has a rosette of 
buds of its own (figs. 69, 71, 73). In buds half-grown and older the stalk, as 
has already been noted, may be slender and attenuated in parts, while short and 
transversely wrinkled in others. These latter parts are sausage-shaped, and 
pinched at one or both of their extremities, and the most plausible explanation of 
the above double rosette of buds seems to be that a full-grown bud may sever 
its stalk at any point, and that not only does the free extremity of that part of 
the stalk which remains attached to the liberated bud possess the capacity of 
developing buds of the next generation, but the free end of the other portion 
* For comparisons of this kind the shield is removed and mounted for examination under the microscope. 
