PLATE XXVI. 
Fip. 1. Mineral particles in the residue of a Globigerina Ooze. Station 300; 1375 fathoms, South Pacific, 
Tliese are essentially of a volcanic nature : in addition to fragments of pumice, easily recognised 
by their structure and the absence of colour, there are homogeneous red-brown particles, vitreous 
fragments altered into palagonite, and also fragments of felspars, augite, and grains of magnetite 
(magnified 90 diameters). 
Fig. 2. Mineral particles of a Red Clay. Station 282 ; 2450 fathoms, South Pacific. AU the particles are 
of volcanic origin. Fragments of felspar may be recognised by the homogeneity and regular frac- 
ture. There are numerous fragments of pumice. The brown grains are particles of palagonite or 
other mineral particles coated with deposits of manganese and iron (magnified 175 diameters). 
Fig. 3. Mineral particles from a Red Clay, Station 165a; 2600 fathoms. South Pacific. In addition to 
fragments of pumice, splinters of felspar, and little green prisms of augite, which are the usual 
minerals in a Red Clay, there are represented in the figure many rounded granules of quartz, for 
the most part covered ■with limonite. The mineralogical nature and form of these granules show 
that they are not a normal element in the Red Clay deposit ; they are believed to be particles 
borne by atmospheric currents from the Australian continent (magnified 175 diameters). 
Fig. 4. Mineral particles from a Globigerina Ooze. Station 303 ; 1325 fathoms. South Pacific. This figure 
shows abundance of glassy volcanic particles, belonging for the most part to the acid and filamen- 
tous variety of pumice, although there are also fragments of the basic variety with rounded pores and 
of a yellow or red-brown colour (magnified 175 diameters). 
I'ig. 5. Mineral particles of a Beach Sand from Diamond Point, Honolulu, Sand'wich Islands. These are 
almost exclusively formed of unaltered crystals of oli'vine, along with some ■vitreous particles. 
Similar particles are -^^udely distributed in the Coral Muds and Sands of the neighbouring coasts 
(magnified 37 diameters). 
Fig. 6. Mineral particles of a Beach Sand from the Admiralty Islands. Among these may be recognised large 
colourless fragments of felspar (plagioclase), prismatic green fragments, more or less irregular, of 
augite, brown fragments of hornblende, dirty brown basaltic lapilli, fragments of palagonite, olivine, 
magnetite, and particles of volcanic glass (magnified 37 diameters). 
