574 Report of the State Geologist. 



isms being Bryozoa, there are yet other points which also oppose 

 such a supposition. One of these is the structure of the walls in 

 the MoNTicuLiPOEiD^ and in the Bryozoa. There are many forms 

 of Bryozoa which deposit carbonate of lime in the ectocyst of 

 their body more or less abundantly. This deposit takes place in 

 the median layer of the ectocyst only, whilst the outer and inner 

 layers remain of a horny nature, which prolDably is the cause that 

 ih thin sections the calcareous walls of single individuals appear 

 separated from each other by dark lines. If we now consider 

 more in detail the structure of the calcareous substance of which 

 the walls of the cells are built, we find that it is composed of very 

 thin fibers placed vertically to the surface of the wall, so that in 

 sections cutting the single cells transversely, a concentric arrange- 

 ment of the fibers can never be observed. These fibers leave 

 interstices between them at intervals, producing numerous capil- 

 lary tubes, by which the walls of the Bryozoa seem always to be 

 pierced in great numbers, if otherwise sufficiently well preserved. 

 Every work on recent or fossil Bryozoa shows this. 



" Of all this there is not a trace in the Motsttculipoeid^. ' 



" The animals of a colony of corals undergo constantly a certain 

 process of renovation. The animal deposits large masses of 

 sclerenchyma behind itself and thus slowly ascends within the 

 tube, sometimes chambering off the dead and useless parts of the 

 corallum by diaphragms or tabulae ; the animals are all self -feed- 

 ing, performing all their vital functions during their whole life- 

 time, at the same time constantly producing new gems. The 

 structure of the wall is in accordance with these peculiarities, 

 the reversedly conical layers of sclerenchyma by which the wall 

 of the McNTicuiiPOEiD^ is built up indicate the ascending move- 

 ment of the animal within its tube. 



"The circumstance that the greater part of the animals of the 

 colony of Bryoza is in a state of latent life, the functions of 

 taking and digesting food being performed by only a few indi- 

 viduals at the top of the branches in arborescent forms, brings 

 with it the other peculiarity, that all the animals of a colony are 

 in intimate connection and communication with each other; this 

 communication seems to be brought about partly by the capillary 



