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 THE CONDOR VoL XV of birds were feeding extensively upon grass- hoppers. Taking into. account' numbers of individuals as well as destructive capacity of each species, the relative importance of the five ablest destr'oyers was as follows: (1) Bi- colored Blackbird, (2) Western Meadowlark, (3) Killdeer, (4) Bullock Oriole, and (5) California Shrike. It is shown that with abnormal increase of such an insect as the grasshopper, many birds appropriate this food source for the time be- ing, and .t once factor in checking the out- break. The principle is emphasized that birds turn to the sort of food most readily avail- able. While figures are given which show conclusively that the birds of the region could not have controlled the plague after once well under way, the author reasons by infer- ence that many incipient insect outbreaks may be checked by birds at the outset, so that they never reach a point where great damage re- sults. In the Los Banos outbreak, the insects had become so abundant locally that the birds when under observation made no noticeable headway against the pests from day to day; but it was possible to figure the value of the birds in hastening the end of the insect raid, and even in lessening the amount of aggre- gate damage sustained at the time. Mr. Bryant's paper is commendable in its accurate detail of fact. More particularly is if admirable in the calm and judicious mode of drawing inductions. There is no discord- ant note of sentimentality to mar the paper as a scientific contribution.--J. GRINNjL. A REviSION OF THE FORMS OF THE GREAT BLuE HERON (kRDEA HERODIAS LINNAEUS). By HARRy C. OBERHOLSER (Proc. U.S. Nat. Mus., vol. 43, December 12, 1912, pp. 531-559). In this treatment of the Great Blue Heron ten geographical races are recognized, four of them being first described here. Descrip- tions, critical comments, and other details of the work are presented with all the painstak- ing care and accuracy characterizing previous contributions of the author, whose series of studies of various difficult groups forms such a valuable portion of the ornithological litera- ture of recent years. The paper under consideration is of espe- cial interest to California ornithologists, in that two of the new subspecies described are from this state. Ardea herodias hyperonca, type locality Baird, California, is the name applied to the form inhabiting California in general, excepting the southeastern desert re- gion and the Santa Barbara Islands. Hyper- onca is distinguished from the Eastern A. h. herodias by its greater size alone, being ex- actly similar in color; as the much paler col. ored treganai occupies the desert and Great Basin regions intervening between the habi- tats of hyperonca and herodias, it is quite logical t6 'recognize in nomenclature the dif- ferences between the two latter forms. As much cannot be said of the island sub- species described. The characterization of Ardea herodias oligista is based upon a single immature bird from San Clemente Island, and such sweeping generalizations are made from the weak basis afforded by this one specimen that it almost appears that the au- thor is giving expression to a preconceived belief that there should be a separate island subspecies, rather than to a dispassionate ex- position of what his material actually reveals. The only difference claimed for the island race is its smaller size. Coloration is de- clared to be the same as in the mainland form hyperonca. The one specimen available, though admittedly .an immature bird, is said to be "evidently full grown". From the date of capture, August 26, this may, perhaps, be questioned. At any rate it is unfortunate that the only character ascribed to the race is one that might be explained by the immaturity of the single specimen examined. The subspe. cies described upon the strength of this one young bird from San Clemente Island is giv- en a range including "Santa Cruz, San Nico- las, Anacapa, Santa Catalina, and probably other islands of the group", although certain of these islands have as little in common with one another as they have with the mainland. We are also told that "this race is prob- ably confined to the Santa Barbara Islands, as the species is said to be resident there". Just what grounds there are for the latter assertion is not apparent, and it is doubtful if the statement could be proved. The islands are such a short distance from the mainland that the intervening channels can be but in- considerable barriers to a strong flying bird like the Great Blue Heron. In the present paper (page 536) we are told of a specimen of A. h. herodias taken at sea about 130 miles off the coast of New Jersey! Furthermore, a favorite feeding ground of the herons abo/t the islands is on the extensive beds. of float- ing kelp, which support the birds easily, and form convenient resting places at short in- tervals, should any such be required. Altogether, even c6nceding the-possibility of the existence of a race of Ardeo herodias confined to the Santa Barbara Islands, we cannot admit it to be proved, nor .even demon- strated to be reasonablg probable, in the paper under discussion, while there are many facts that argue against it. The description of the subspecies oligista seems ill considered, and is an undoubted blemish in what appears to be in other re- spects an excellent piece of work. It would