PREFACE. 



ONE year elapsed after these drawings had been completed before it was 

 decided that they should be published. 



This decision was greatly influenced by the encouraging remarks of one 

 of the most skilled naturalists and microscopists in Ireland ; part of whose 

 letter is here quoted, as an appropriate Introduction to this little work : 



" The interest that attaches to the subject of minute organisms at great 

 depths, justifies the publication of any contributions on the subject, however 

 small. Your labours have not been small. Whether you may or may not have 

 discovered forms new to science, is a matter of little consideration : a new field 

 is opened up to research, and it is something to stimulate enquiry. This is 

 the least good likely to result from your publication. As to Diatoms, you have 

 brought up three forms not previously described, and if to other departments 

 your success has been equal to this, your labour has not been in vain. 







" ' Macta puer virtute.' 



" Let no man deprive you of the honour you have won, but cultivate assiduously 

 the field you yourself have opened, and you shall have your reward." 



WEYMOUTH, DORSET, 

 1870. 



