VI PREFACE. 



mucli-valuecl privilege of consulting her respecting marine 

 Algse; and was ready at all times to favour me with specimens. 

 The preUminary chapters^ extending to a greater length 

 than I anticipated, will not, I trust, be regarded as altogether 

 uninteresting. In the body of the work, I can safely recom- 

 mend the description of genera, being chiefly taken from 

 the valuable works of Dr. Greville and Professor Harvey. 

 The plates are by Mr. Eitch, whose talents in this depart- 

 ment are too well known to need praise from me. The 

 plates add greatly to the value of the work, by making 

 verbal descriptions much more easily understood : — 



" Segnius irritant animos demissa per aurem, 

 Quam quse sunt oculis subjecta fidelibus." 



Though the work is intended for beginners, I shall 

 venture to hope that some portions of it may not be quite 

 devoid of interest to proficients in science. The savans of 

 the south may not disdain to listen even to a sciolist of the 

 north-west, when, without pretension, lie records his own 

 observations. 



