e 
THE GENETIC RELATIONS OF THE CETACEANS. 19 
The animal itself, on account of its minute size, is seldom 
seen; and the uninitiated, when first troubled with it, are often 
alarmed at the symptoms and at a loss to account for them. For- 
tunately, these little plagues never attach to persons in such im- 
mense numbers as do sometimes young or so-called ‘‘seed” ticks; 
but I have known cases where, with irritation and consequent 
scratching, the flesh had the appearance of being covered with 
ulcers; and in some localities, where these pests most abound, 
sulphur is often sprinkled, during “ jigger ” season, in foot-gear as 
a protection. 
Sulphur-ointment is the best remedy against the effects of either 
of these mites, though when that cannot be obtained; a 
water, and salt water will partially allay the irritation. 
The normal food of either must, apparently, consist of the 
juices of plants, and the love of blood proves ruinous to those 
individuals who get a chance to indulge it.. For unlike the true 
chigoe the female of which deposits eggs in the wound she 
makes, these harvest bugs have no object of the kind, and, when 
not killed at the hands of those they torment, they soon die — 
victims to their sanguinary appetite. 
ON THE GENETIC RELATIONS OF THE CETACEANS 
AND THE METHODS INVOLVED IN DISCOVERY. 
BY THEODORE GILL, M.D., PH.D. 
In a “Synopsis of the Primary Subdivisions of the Cetaceans,” 
published in 1871,* I ventured some remarks on the apparent ge- 
netic relations of the Cetaceans, and observed that ** between the 
Carnivores and the Cetaceans of the present age, the gap does 
indeed appear to be very great, but it is bridged over, to a very 
considerable extent, by the Zeuglodonts of the Tertiary epoch, 
. . .,- and from the Zeuglodont stem have probably descended, in 
different directions, the toothed and whalebone whales; while the — 
former, in some features, such as the general form of the skull, 
the teeth, etc., appear to deviate less from ordinary mammals ; the 
latter, in other se ese but especially in the development of — a 
D 
>P Ji d Coi ications Essex Inst. L vi, pp- 121-126. 
