136 RlilPORTS 01? INVESTIGATIONS AND PROJECTS. 



All of the young of the Favia fragum were attached to the bottom of the 

 dish, which has been suspended in a wire cage from a floating live-car and 

 anchored off Loggerhead Key. » . . 



This seems to be the first attempt to rear corals from the young. As it is 

 a new project, the methods of experimentation had to be devised, and it ap- 

 pears that they have been discovered. The initial experiments indicate suc- 

 cess in the undertaking. In subsequent years attempts will be made to obtain 

 the young of all the species represented in the Tortugas region, and to plant 

 attached young of the same species under different environments, so as to 

 observe the influence of change of environment on variation. 



One of the subjects that has attracted attention of the students of Madre- 

 poraria is the means by which distribution is effected. As is well known 

 most corals thrive best in regions of considerable current. One planula of 

 Porites astreoides was free for about 7 days. The duration of the free- 

 swimming larval stage in Pavia fragum ranged between 5 and 12 days. 

 These data show that currents are probably able to effect wide distribution. 

 The rate of the Gulf Stream is estimated at approximately 3 miles per hour, 

 which is 72 miles per day. The maximum observed duration of the free 

 larval stage of Pavia fragum was 12 days. This would indicate the possibil- 

 ity of a larva of Pavia fragum drifting over 800 miles. 



A Collection of Hydroids Made at the Tortugas, during May, June, and July, 

 igo8, by W. Seivard Wallace. 



The greater portion of my time while at the Laboratory was devoted to 

 collecting and, as far as time permitted, studying and sketching, the hydroids 

 of the region. In general it can be said that there is a fairly abundant hydroid 

 fauna, specially of the smaller and more delicate forms of the Plumularidse 

 and Campanularidae ; and this is not remarkable, considering the large num- 

 ber of medusae found to occur here. 



Collecting was carried .on in the usual way, by dredging, raking bottom, 

 scraping and examining the algae, sponges, gorgonians, docks, boats, live- 

 cars, and submerged objects generally. It was kept in mind that the hydroids 

 are found at all depths, in all sorts of situations, and that their colonies are 

 very often disguised by parasitic growths of other hydroids, of algae and par- 

 ticularly the Suctorians, such as Podopheya, hiding the true character of the 

 growth. '. ! 



Speaking broadly, about 50 or more species were collected, most of them 

 common to the Bahama-Florida region, but some are of considerable interest 

 because of their rarity. Several of the new species described by Prof. C. C. 

 Nutting in his Hydroids of America were identified, among them Aglao- 

 phenia contorta, Monotheca margaretta, Plumularia merniis, Plumularia al- 

 ternata, Sertularia versluysii (new name), and others. In the latter case, if 

 the identification is actual, I shall be able to add the description of the gono- 

 some. As considerable of the material collected was not examined thor- 

 oughly, doubtless the estimate of 50 species is a low one. 



Plans to construct a table of depths and habitat may be frustrated by the 

 widely scattered situations in which certain hydroids are found, Halopteris 

 carinata, for example, being found in all dredging depths from 3 or 4 fath- 

 oms up to 18 fathoms, while Halecium sessile is found everywhere in freely 



