26 INTRODUCTION. 



perceptible^ as small dots, by the naked eye, but when seen 

 tlirough a pretty powerful lens they were perfectly circular 

 and of beautiful workmanship, and not unlike some of the 

 figui'es of Lesmidiea. These in general were green, but a 

 few were reddish- brown ; and last of all there were a 

 number of very minute branched Algsc, just perceptible as 

 a faint haze by the naked eye, but when examined by a 

 lens they were more like exceedingly diminutive specimens 

 of Sphacelara filicina tlian anything I remember, though 

 I do not at all think that they were the young of this plant. 

 The branches adhere, closely all along to the glass, spreading 

 in all directions from a centre, though not with very uniform 

 reffularitv. The more advanced branches seem to lose their 

 pinnse towards the point ; they, and most of the others, are 

 still alive in the tumbler, which would form a studio not 

 unworthy even of Mr. Ealfs. The difficulty with me, 

 besides want of time, is how to remove such exceedingly 

 minute and delicate structures so as to bring them under 

 the field of the microscope. Much do I wish that they were 

 in the hands of a good microscopist, to examine them, and 

 still more minute VorticeUce which in beautiful tufts are 

 mingled along with them, but so small that a tuft of thirty 

 is not perceptible, even as a haze, by the naked eye. I 



