94 Rev. T. Hincks's Critical Notes 



there is no doubt room for critical revision of the details of 

 the current classification and for such readjustment as may 

 be rendered necessary by our increased knowledge of specific 

 forms and may tend to make it a more complete expression of 

 its fundamental principle. And T may say in passing that I 

 am very sensible of the service which Dr. Jullien has ren- 

 dered by his enthusiastic and uncompromising loyalty to that 

 principle, though I am unable to accept the special scheme of 

 classification which he has associated with it. 



To Dr. Koschinsky we are indebted for a valuable critique 

 on a number of Cheilostomatous genera, in which he suggests 

 some modifications of the existing groups and constitutes a 

 number of new ones. 



Some of the changes which he proposes seem to me to be in 

 every way worthy of consideration. The enormous increase in 

 the number of described species within the last few years would 

 alone render some revision of the genera absolutely necessary. 

 We are now in a much better position for determining the pre- 

 cise value of the characters employed in diagnosis, and have a 

 much larger knowledge of the modifications of the generic types. 

 A group which might seem sufficiently isolated and distinc- 

 tive, when represented by only two or three species, in which 

 the diagnostic characters are clearly and strongly marked, will 

 present a very different aspect when it includes a multitude of 

 forms, amongst which the common characters may have been 

 more or less obscured and variously affected by ceaseless 

 modification. 



As our knowledge widens the lesson is pressed upon us 

 with added force that we cannot isolate plots of the great 

 genealogical network and shut them up within hard-and-fast 

 lines, but must be content with a large amount of indefinite- 

 ness in our system, in view of the infinitely varied and 

 complex relationships of organic life. 



While I am unable to accept all Dr. Koschinsky 's criti- 

 cisms, I freely admit that there is much force in many of 

 them and that he has established a case for the reexamination 

 and revision of some of the existing groups. 



Section 2. Family Cribrilinidse, Hincks. 



Syn. Fain. Costulidcs, Jullien, Bull. Soe. Zoologique de France, t. xi. 



(1886). 



In his paper entitled " Les Costulidees, nouvelle Famille 

 de Bryozoaires," Dr. Jullien proposes a new classification of 

 the forms which have hitherto been ranked in the family 

 Cribrilinidce, Hincks, including the genera Membraniporella } 



