VINE : CLASSIFICATION OF THE PALAEOZOIC POLYZOA. 
29 
Mr. Ulrich established a new sub-order which he named and described 
as follows : — 
Sub-order Trepostomata, Ulrich. 
''This sub-order is proposed for the reception of the majority of 
the Palaeozoic, and many of the more recent Bryozoa. The principal 
distinguishing features of the sub-order are : — (1.) That the Zoarium 
is composed of slender fasciculate tubes, which do not (as is the 
case in the Ctjclostomata,) gradually enlarge as they approach the 
surface, but romaia throughout nearly of the same diameter ; and 
(2.) That at a certain point in the course of the tubes to the surface, 
they bend outward, more or less abruptly, and change in character." 
Five families in particular Mr. Ulrich places in this sub-division. 
They are v — 
1. Family Ptilodictyonidae, Zittel emend, Ulrich. 
2. ., Stictoporidee, Ulrich. 
3. „ Monticuliporid?e, Xicholson. 
4. Fistuliporidfe, Ulrich. 
5. Ceramoporidee, Ulrich. 
In the first family is placed the Genus Ptilodictija, Lonsdale, 
and in the second the Genus Cystodictya, Ulrich, but both are differ- 
ently characterized in the descriptions. In the Ptilodictya the exter- 
nal features are diagnosed, but in Cystodictya the external and 
internal features are characterized, " Sections show that the inter- 
tubular spaces are occupied by a vesicular tissue.""^' It is very evident 
therefore, that Mr. Ulrich accepted for his generic divisions very 
different characters from myself, he tiie structure of the Zoarium, I 
the character of the Cell only, and there could be no offence in placing 
my name Arcampora, as a synonym of Cystodictya,^ Ulrich, if the 
priority had been Mr. Ulrich' s instead of my own. My placement, 
then, of two different Genera, Flustra 1 parallela, Phillips, in 
close companionship with Ptehdictya is not the result of ignorance, 
but rather on account of the partially hidden cell, and so on with 
Glamonome disticha, Goldfuss. If, therefore, we are to depend upon 
the structure of the interspaces, all of which were well known to me 
* Ulrich, op. cit., p. 152 
t Jour. Cincin. Soc. Nat. Hist , April, 1884. 
