yaw YORK SHELL CLUB NOTES No. 240 March 1978 Page 5 
and the key to age determination is the growth rings of the she ; 
Near Kukak Bay (Alaska) I found the wery neni far erin t. tee 
with all the bright sunrise and sunset colors on the inside of the 
shells. I saved a few specimens and studied them in relation to the 
age-growth studies I was making. Apparently some of them were very 
old. The winter marks were definite and consistent. If my readings 
were correct some of my specimens were 45, 46, and 47 years old. © 
One mark disturbed me. It appeared to be two winter rings close to- 
gether, and could have been caused by an unusual climatic condition 
or a heavy storm locally. Counting back from the edge I concluded 
that the evidence indicated the year 1912, and the time as being in 
the spring about the time the clam started to grow. 
I then dug a large number of specimens of all ages. On each shell I 
found what I came to call "the 1912 mark." Shells which were not old 
enough to go back to 1912 had no double rings. Therefore, the cause 
must have been something that happened only once in the last 47 years. 
After some time I asked an old-timer in the community what had hap- 
pened in the spring of 1912. Immediately he began to tell me of the 
Katmai eruption in April 1912. At night a great volcano stood in 
the local mountain chain. In the morning the entire mountain had 
been blown away and only a big hole remained at the spot. Ashes fell 
on the roofs of Kodiak, 80 or more miles away, and crushed them. All 
summer the water for miles around was covered with ash and pumice. 
Nothing grew normally; not only the shells, but the trees were also 
marked. 
I then had no doubt that the annual ring method of age determination 
was sound. People that claimed the ages could not be determined 
accurately from shells had only failed to learn to read .ecseeres 

REVIEWS: D 
MOLUSCOS DEL GOLFO SAN MATIAS 
(Rio Negro Province, Argentina) by Victor Scarabino. Comunicaciones 
de la Sociedad Malacologica del Uruguay, V¥Ol «4, ‘nos. F152 1197 6 
1977 (Spanish, brief English summary). 
One hundred twenty-five mollusks are keyed out, illustrated, and 
ranges given. This is an excellent local account which includes ex- 
cellent keys for identification and fine, recognizable line drawings 
of most of the species mentioned. Each species is provided with a 
synonymy, an account of its range, and the precise habitat it inhab- 
its within the Gulf of San Matias. Although mimeographed, this is. 
&a splendid piece of work which deserves a place in every malacologi- 
cal library. 
Mewes issue includes an obituary of the well-known Argentine 
malacologist Alberto Carcelles (1897-1977) by J. J. Parodiz and a 
list of the malacological works he published. 
Non-subscribers to the COMUNICACIONES who wish to obtain a copy 
should contact: Jorge Pita, Casilla de Correos 1401, Montevideo, 
Uruguay. 

It is pleasant to report the appearance of four more numbers of the 
valuable and ‘ibereonine OCCASIONAL PAPERS ON MOLLUSKS published by 
