2 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



prolific diversity of forms is more often met with in warm waters. 

 In the Philippine flora there seems to be in this abundance of genera 

 a fairly even gradation maintained that corresponds io the relative 

 size of each genus. Thus of the large genus, Biddulphia, 70 species 

 are recorded here; the enormous genus Navicula is represented by 

 149 species; Coscinodiscus is somewhat below its average with 36 

 species; Campylodiscus somewhat above with 47 species; the genus 

 perhaps showing a markedly strong development is Amplwra, which 

 contributes the relatively large number of 56 species. Of course the 

 many gatherings here included vary greatly in this respect ; some are 

 made up principally of round forms, others are decidedly Amphora 

 gatherings, etc. 



There is here only occasional mention of strictly plankton diatoms, 

 as no plankton gatherings were available for this investigation; and 

 the few species recorded, chiefly Chaetoceros and Rhizoselenia, were 

 stray individuals found in dredged samples, where a few plankton 

 specimens would necessarily be expected. 



Next to the diatoms, the most abundant microorganisms were 

 found to be the radioiaria and the spicules of sponges. As to foram- 

 inifera, no estimate of their abundance was possible, because a careful 

 survey of the material was not undertaken until after it had been 

 prepared for diatom study by boiling in acids to remove the organic 

 matter. This process, which leaves unaffected the siliceous diatoms, 

 radioiaria, and spicules, destroys the calcareous foraminifera, together 

 with all the softer organisms, such as copepods, annelids, nematodes, 

 etc. But the preliminary examinations made to determine which 

 samples were diatomaceous enables me to say that foraminifera were 

 present in most of them and in some they were abundant. 



I regret to have to record that the exact location of most of the 

 Philippine Island dredgings examined for this paper can not be given. 

 The labels, usually attached to the neck of the bottles of Albatross 

 specimens, sometimes included on a slip of paper within the bottle, 

 were in nearly every instance lacking. Those who made the collec- 

 tions can find no explanation for this omission. In one or two bottles 

 fragments of labels were found, but in most cases there was not even 

 a trace of paper fiber discoverable under the microscope. But it is 

 the unfortunate absence of these labels, and not the reason for their 

 absence, that is of importance. The date of collecting, depth, and 

 exact place on the coast where each sample was obtained are therefore 

 wanting. It can however be said that these bottles without labels 

 were unmistakably Philippine Island dredgings, as the letter P was 

 in every case painted upon the cork of the bottle. The nature of the 

 material in most cases, and especially in the samples richest in dia- 

 toms, indicated that they were bottom samples taken in shallow bays 

 or harbors rather than along the more exposed parts of the coast. 



