144 MR. A. E. FINCKH. 



exjDansion. Measurements were taken in four different directions, and these indicated 

 an average rate of extension of remarkable rapidity, i.e., 1 inch in 13 '5 weeks. 



(5) P. verrucosa. At the time of the commencement of the experiments no 

 specimen of this sj^ecies was found large enough to allow of its being weighed under 

 water on the heavy calibre scales, which alone are suited for such work. Resort, 

 therefore, was had to fragments, and these, to suit the scales, could not be more 

 than 500 grains in weight. Here, as in all cases where small broken-off pieces were 

 used, a most startling increase was noted. In this one it amounted to 150 per cent. 

 per annum. 



In reference to this and all other similar large increases, it must be stated that on 

 all broken-off pieces the entire fractured surface was found to become rapidly coated 

 by a continuation of the general fleshy ccenosarc of the coral, a coating which soon 

 gave rise to polyps, so that the increase in weight is by no means due to a natural 

 growth of the coral. The fractured surface gave an additional area for growth which 

 was not present under natural conditions. This undoubtedly indicates that the 

 method of weighing is, under these circumstances, by no means a trustworthy source 

 of information in regard to the rate of growth. 



(6) P. paucistellata. In the case of this tiny coral a similarly large increase was 

 experienced. For the reasons above stated not much importance is to be attached 

 to the result. 



(7) Montipora incoynita. A specimen of this inushroom coral was kept under 

 observation. Measurements in three different directions showed an average increase 

 of 1 inch in 35 '7 weeks. In one of the directions measured the increase in three 

 months was as much as half an inch.""' 



(8) Millepora alcicornis. This branching stinging Millepore offers great facilities 

 for the observation of its growth. When its smooth laterally-compressed branches 

 come in contact with an opposing one, firm imion takes place. Between such 

 approaching surfaces very accurate measurements can be taken. An average increase 

 of 1 inch in 3 4 '7 weeks was observed. 



Besides actual growth, this hydrocoralline was noted to have a marked tendency 

 to coat, with its own calcareous material, any object with which it comes in contact. 

 The specimen, on which the above growth was determined, in two months completely 

 covered the cord by means of which it had been fastened down. On the same piece 

 some fragments of Halimeda, which had become entangled in it, were entirely 

 coated over.f 



(9) M. complanata. This massive ridge-like hydrocoralline was unfortunately not 

 of frequent occurrence near the camp. The small broken-off pieces obtained showed 

 an increase of 16 '5 per cent, per annum. This result was not considered satisfactory, 



* The specimen is in the collection forwarded to London, 

 t The specimen is in the collection forwarded to London. 



