UTILIZATION OF THE FISH WASTE OF THE PACIFIC OCEAN. 53 
cannery waste into fertilizer, and adequate supplies of these are 
found near certain of the centers of the salmon-canning industry. 
It originally was supposed that the rendering of the cannery waste 
could be made to serve as an auxiliary operation to the treatment of 
kelp. After investigation it appears more probable that it would 
be found necessary to make the curing of kelp supplementary to the 
rendering of fish waste, since the apparatus required for the latter 
is much more elaborate than that for the former. 
The term " kelp," formerly applied to the ashes of seaweeds, now 
has come to mean any of the brown marine alga?. In general use its 
meaning has become restricted to the large and conspicuous sea algae 
of the Pacific coast. The so-called giant kelps of the Pacific coast 
may be defined as four species of the marine algee, whose botanical 
names are Pelagophycus porra, Alaria fistulosa, Nereocystis luet- 
kea?ia, and Macrocystis pyrifera, named in the reverse order of their 
present economic importance. Only two of these, the latter tw r o, at 
present should be considered in a fertilizer connection, as of the 
former two, the Pelagophycus porra occurs in too small quantities 
to be important, though it carries a very high proportion of valu- 
able fertilizer ingredients, and the Alaria fistulos-a is too low in 
potassium to merit treatment where the other kelps are available in 
sufficient quantities. 
The Nereocystis is an annual whose seasonal growth attains an 
average of 50 feet. The rapid growth necessary to reach such a size 
in a growing season denotes an abundant supply of the elements or 
compounds which enter into the plants' metabolism, and this, in turn, 
indicates a large and constantly changing volume of the medium in 
which it grows. Thus it is found in localities of heavy surf or strong 
tideways. To maintain itself in position under these conditions it 
must attach itself firmly to the bottom. Therefore a rocky bottom is 
essential to the establishment of groves of the plants. To attach 
itself, the plant develops a "holdfast," a rootlike growth which 
tends to grow around and grasp the objects with which it comes in 
contact, thus anchoring the plant. Extending upward from the 
holdfast is the stipe, a long, slender stem, cordlike and tough, which 
reaches almost to the surface of the water. Toward its upper end 
it gradually enlarges, becoming hollow, and culminates in a hol- 
low bulb. This portion, being air filled, serves to float the plant, and 
is called the pneumatocyst. The plant thus is lifted and held in 
the sunlight. From the top of the pneumatocyst develop tw T o tufts 
or bunches of long, ribbonlike leaves, called fronds, which grow 10 
or 15 feet in length and trail out in the tidal currents. The most in- 
teresting characteristic of the plant, and a characteristic that dis- 
tinguishes it from the other important kelp, the Macrocystis, is that 
almost the entire plant, on the basis of weight, lies on or at the 
