1875.] REY. S. J. WHITMEE ON PALOLA VIRIDIS. 499 
the Palolo on the morning of the 12th, when the moon quartered. 
In this I was not disappointed. ‘They were more abundant this 
year than they had been the previous one. I confined my attention 
almost entirely to the contact of the worms with each other, and to 
their breaking into pieces. Early in the morning I caught three 
green and three brown ones, and placed them in a large glass vessel 
which I had provided for the purpose. While observing the worms 
which were swimming freely in the sea, I also kept my eye upon my 
captives. I saw no sexual contact either between those in the vessel 
or those in the sea. They all went gyrating about until a little after 
sunrise. Then I observed those in the vessel begin to break, first into 
long pieces, each example separating into two or three parts, while 
these pieces continued to subdivide into minute portions. I observed 
those in the sea divided in the same manner and at the same time. 
This continued till about 8 o’clock a.m., by which time those in the 
sea had nearly disappeared. The six worms in the vessel were also 
completely broken up, the water (about half a gallon) being rendered 
somewhat turbid, as if a dessert-spoonful of milk had been mixed 
with it. The green ova were floating in all parts of the water, but 
were gently settling towards the bottom. The empty cysts of the 
defunct worms were lying on the*bottom of the vessel. I brought 
them home with me, and emptied the whole into a small aquarium, 
which I am leaving undisturbed to see if the eggs will develop there*. 
By the time I reached home, about 1 p.., all the ova had settled to 
the bottom of the vessel, notwithstanding the constant agitation of 
the water by the motion of the boat in which I brought it. 
I wish specially to direct attention to the following interesting fact 
respecting the appearance of the Palolo. Although it comes only 
at one particular state of the moon (the time of the last quarter), it 
still keeps solar time in the long run. As far as I have certain 
information, it has only heen seen in October, November, and occa- 
sionally, but very rarely, in December. Nowit is evident that if the 
intervals between its appearance were regularly 12 lunations, the 
months during which it is found would be constantly changing, since 
it would appear about 11 days earlier each year. If, on the other 
hand, the intervals were regularly 13 lunations, it would come about 
18 days later every year, and the months of its appearance would 
change still more rapidly. 
Having only lately given any attention to this matter, it was with 
considerable surprise I discovered, from the dates of its appearance, 
that in each period of three years there are two intervals of 12 luna- 
tions each, while in one interval there are 13 lunations. Unfor- 
tunately the observations given in the early part of this paper were 
not all consecutive, so that I cannot say positively that the length 
of the intervals proceeds in regular order, two years of 12 lunations 
being invariably followed by one of 13 lunations ; but the rule holds 
good in the aggregate of 12 years over which the observations 
extend, there being 8 years of 12 lunations each, and 4 years of 
13 lunations each. This will appear from the following table, in 
* P.S. They did not develop in the aquarium.—March 17, 1875. 
32* 
