362 Forty-first Report on the State Museum. 



period, and if once allowed to drop out of the line of work in pro- 

 gress it will be extremely difficult to revise it, and it can never again 

 be continued under so favorable conditions as tlie present, when 

 everything is forwarded and the subject fully occupying the minds 

 of those engaged in the work. The number of species described 

 in volume VI is 385, and the number of genera 72. 



The following synoptical table presents the names of genera 

 and species therein contained, and will also serve to show their 

 geological relations. 



Both for want of space and time, the author has made no attempt 

 to present a classification of the compact, massive or branching 

 forms of the so-termed Bryozoa. Such a work can only be satis- 

 factorily presented after much more careful study of the interior 

 structure, the mode of growth, and the conditions supervening 

 from origin to maturity. Such a classification however is very 

 important, and until that be done the descriptive portion of the 

 work can only be regarded as a step in the progress of research, 

 which may serve a useful purpose — the final presentation of our 

 results. 



