May 29, 1896.] 



SCIENCE. 



823 



found especially in the ' Martinez group' (an 

 upper sub-division of tlie Cbico), and in ' in- 

 termediate beds.' A study of the faunas and 

 stratigraphy, especially in middle California, 

 has proved that the intermediate beds 

 and the upper part of the Martinez group 

 are identical and that they form a lower 

 zone of the Tejon, or Eocene. When the 

 line between the two formations is thus lo- 

 cated their faunas are but little more closely 

 related than the Upper Cretaceous and Lower 

 Eocene faunas of other parts of the world. 

 With the exception of an Ammonite, of which 

 a few specimens were reported from the Tejon 

 in early collections, the few species that seem 

 to be identical in the two formations are per- 

 sistent types that have come down to the 

 present day with little change. 



Tlie Structure and Age of the Cascade Range: 

 By J. S. DiLLEE. The two sections of the 

 Cascade Eange afforded by the Klamath and 

 Columbia Rivers expose volcanic rocks only 

 and indicate that the range where most typi- 

 cally developed is composed essentially of lava 

 from top to bottom. As far as yet known, it 

 has no core of older metamorphic rocks on 

 which the line of volcanoes developed. 



He desci'ibed the position and relations of the 

 auriferous slate series. 



At Ashland, in southern Oregon, the relations 

 of the Cascade Range to the Klamaths is better 

 exposed. They are separated by Rogue River 

 Valley, which is cut chieflj'^ in Cretaceous strata. 

 Overlying these with apparent conformity, and 

 dipping gently to the eastward beneath the Cas- 

 cades are similar sedimentary rocks containing 

 silicified wood, referred by Knowlton to a 

 period certainly later than the Cretaceous. 

 Above these and conformable with them on the 

 western slope of the Cascades are numerous 

 sheets of lava and tuff. One sheet of tuff near 

 the base of the series contains Miocene leaves. 

 Although the volcanic activity of the Cascade 

 Eange may have been initiated in earlier times, 

 the period of greatest eruption and the upbuild- 

 ing of the range occurred in the Neocene. 



An Early Date for Glaciation in the Sierra 

 Nevada: By Willaed D. Johnson. The author 

 described the occurrence of striated pebbles, of 

 foreign material, in the extensive andesite-tuff 



flows, or volcanic mud flows of the Sierra, and 

 gave reasons for regarding the striation of these 

 included pebbles as probably glacial. He then 

 called attention to a certain anomalous topog- 

 raphy of the summit region of the range, and 

 o|fered for it an interpretation which, together 

 with the presence of the presumably glacial 

 pebbles in the deeply canyoned lavas, appeared 

 to warrant the inference that glaciation here 

 had a beginning coincident with the erection of 

 the Sierra Nevada into a high range. 



W. F. MOESELL. 



TJ. S. Geol. Suevey. 



ACADEMY OF NATUEAL SCIENCES OF 

 PHILADELPHIA. 



May B, 1S96. — Dr. F. P. HENEYmade a com- 

 munication on Filaria sanguinis hominis noc- 

 turna specimens of which had been obtained 

 from the blood of a patient sufiering from chy- 

 luria due to clogging of the lymphatics by the 

 ova of the parasite. The various forms of the 

 worm and their life history as given by Dr. 

 Patrick Manson were dwelt on. The parasite 

 secretes no toxine and its presence in man is 

 usually not productive of bad effects. The 

 speaker stated his belief that the excretory 

 products of parasites are hurtful to man in pro- 

 portion to the lowness of their organization. 

 The nocturnal Filarise appear in the superficial 

 vessels about sunset and disappear about the 

 time of rising. In patients induced to sleep 

 during the day the periodicity is reversed. The 

 only treatment is prophylactic as a drug which 

 would kill the mature worm would, in all prob- 

 ability, be hurtful to the host by causing ab- 

 sesses around the dead product. 



Dr. Leonard, in continuation, dwelt on the 

 morphology of the worm, illustrating his re- 

 marks by means of fine micro-photographs of 

 the specimens described by Dr. Henry. 



May 12. — Dr, Charles S. Dolley- described a 

 centrifugal apparatus for the quantitative deter- 

 mination of the food supply of oysters and 

 other aquatic animals which he called a Plank- 

 tonokrit. By means of its use he is enabled 

 to make a large number of plankton estimates 

 in a day and thus judge of the characters of 

 given areas of water in connection with fish 

 and oyster culture at diflerent times of the day, 

 states of the tide, varying depths, etc. 



