644 



SCIENCE 



[N. S. Vol. LI. No. 1330 



^aces are evidently rubbed on one another and thus 

 triturate the substance of the food pellet, only 

 small portions of which are ingested at a time from 

 the trophothylax. In all Pseudomyrmine larvae 

 and in many larvae of the other subfamilies, except 

 the Dorylinse and CerapachyinEB, the trophorhinium 

 js beautifully developed, although in many ants 

 ,(Ponerinse) it must be used for comminuting parts 

 of insects given directly to the larvae by the work- 

 ers. In its development the trophorhinium bears a 

 strange resemblance to the stridulatory organs of 

 ,the petiole and postpetiole of many adult ants. 

 Jt may, in fact, function also as a stridulatory 

 organ, when the food supply is exhausted, and thus 

 apprise the worker nurses of the larva's hunger. 

 Many ant-larvae, notably those of the Ectatommiine 

 PoneriuEB and of most genera of FormicinsB, also 

 have elaborate but coarser stridulatory surfaces on 

 the mandibles, so that the larva may be able to 

 produce a variety of sounds and therefore com- 

 jnunicate to the nurses more than one need or 

 craving. 



, On correlation of shape and station in fresh 

 water mussels: A. E. Oetmann, Ph.D., Sc.D., cu- 

 rator of invertebrate zoology, Carnegie Museum, 

 Pittsburgh. "Various observers have noticed that 

 freshwater mussels differ in shape according to the 

 localities from which they come, and that, gener- 

 ally speaking, flat or compressed shells are found 

 in the smaller streams, more swollen shells in the 

 Jarger ones. But these observations have been 

 rather vague and indefinite. The present paper is 

 devoted to the demonstration of this fact by care- 

 ful measurements and their tabulation on the hand 

 of abundant material from a great number of lo- 

 calities, and it has been found, indeed, that for 

 ^certain species, such a law does exist, according to 

 ,which more swollen specimens are found down- 

 stream, in the larger rivers, more compressed Sipeci- 

 jnens more upstream, and that in the intermediate 

 stretches of a river, these extremes are connected 

 ,by gradual transitions. 



Evolution principles deduced from a study of 

 the even-toed Ungulates, Tcnown as Titanotheres : 

 Henet Fairfield Osbokn, Sc.D., LL.D., research 

 professor of zoology, Columbia University. 



The Astropotheria: William B. Scott, Sc.D., 

 LL.D., professor of geology, Princeton University. 



The middle Cam'brian beds at Manuels, New- 

 foundland, and their relations: B. P. Howell, Je., 

 P.S., instructor in geology, Princeton University. 

 (Introduced by Professor W. B. Scott.) The beds 

 of Middle Cambrian age at Manuels, near St. 



Johns, southeastern Newfoundland, are part of a 

 once widespread sheet of marine sediments, de- 

 posited millions of years ago off the shore of an 

 ancient continent, which probalbly stretched across 

 jwhat is now the North Atlantic Ocean and for 

 hundreds of thousands of years formed a land 

 bridge between such parts of North America and 

 Europe as were then above the sea. These beds are 

 of special scientific interest because they contain 

 large numbers of unusually well-preserved fossils, 

 which prove that the creatures that swarmed in the 

 waters then covering much of what is now New 

 England, southeastern Canada and southeastern 

 Newfoundland were of practically the same sort 

 as those living in the seas which at the same period 

 washed over many parts of Scandinavia and the 

 British Isles. North America has probably been 

 joined to Europe in this way several times in the 

 geologic past, eo that the animals living in the 

 coastal waters could spread from the one hemi- 

 sphere to the other ; but it is seldom that geologists 

 discover such clear evidence of one of these old 

 connections as that which is presented by the 

 Manuels fossils. 



The Michigan meteor of November S6, 1919. 

 Also the glacial anticyclone and the blizza/rd in re- 

 lation to the domed surface of continental glaciers : 

 William H. Hobbs, D.Sc, Ph.D., professor of 

 geology. University of Michigan. 



On Saturday evening the annual dinner of the 

 society was held at the Bellevue Stratford Hotel 

 and was largely attended, the following toasts be- 

 ing responded to: 



The memory of FranTcUn: Hon. Oscar S. Straus. 

 . Our universities: Dr. John M. Clarke. 



Our sister societies: Dr. Harvet W. Wiley. 



The American Philosophical Society: Peopessoe 

 Leslie W. Miller. 



Arthur W. Goodspbed 



SCIENCE 



A Weekly Journal devoted to the Advancement o( 

 Science, publishing the official notices and pro- 

 ceedings of the American Association for 

 tJie Advancement of Science 



Published every Friday by 



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LANCASTER, PA. GARRISON, N. Y. 



NEW YORK, N, Y. 



Entered m die poM-WEc* *l I innrtw. Pi., u Hcaod cU« nalMi 



