Ai'ML 1, 1904.] 



SCIENCE. 



555 



sturgeons would cause one to look for them 

 especially. So Jordan and Evermann (Bul- 

 letin 47, U. S. ]Sl. M., Pt. 1, p. 101), in their 

 characterization of the Polyodontidse, say 

 definitely, ' no barbels.' Only within the last 

 few weeks I have discovered what is seemingly 

 the only reference to these barbels, in a paper 

 by Mr. Edwards Phelps AUis, Jr. (Zoologische 

 Jahrbucher, Abth. fiir Anatomie, etc., Vol. 17, 

 p. 671). 



In a specimen of Polyodon 85 cm. long, 

 these barbels lie 47 mm. in front of the mouth, 

 on the ventral surface of the ' paddle.' They 

 are 23 mm. apart, and the right one measures 

 3.5 mm. in length. The left one is consider- 

 ably shorter, and in general there is consider- 

 able difference in their size in different indi- 

 viduals. They are very slender, nearly 

 colorless, and translucent. It seems doubtful 

 whether they are functional. 



The fact that these barbels have not here- 

 tofore been noticed even by our best systemat- 

 ists suggests the idea that they may not be 

 present in specimens from other regions. As 

 to this point I hope to gather evidence next 

 summer, in connection with other researches 

 on Polyodon. 



Another interesting point concerning 

 Polyodon is the occurrence of peculiar small 

 true scales over the surface lying over the 

 entire scapular arch and extending forward 

 the entire length of the isthmus. They thus 

 form a barrier that must be crossed to enter 

 the branchial region from behind. As this 

 entire region is well covered over by the large 

 opercular flaps aiM gular pouch, it was at first 

 very difficult to see any significance in such 

 an arrangement. But a few observations in 

 the field soon disclosed the meaning. Polyodon 

 is preyed upon, more than any other fish I 

 know of, by the lampreys. To find from ten 

 to fifteen of them attached to one paddlefish 

 is not uncommon, and there is scarcely an 

 individual that bears no scars. Once or twice 

 I observed the lampreys had worked their way 

 under the opercular flaps. Now these, if they 

 worked further forward would encounter the 

 band of scales which would undoubtedly stop 

 them, to judge from their avoidance of scaled 

 areas on other fishes. An examination, how- 



ever, shows that just inside of this band lies 

 the great branchial artery, but little below the 

 surface. It is evident, therefore, that this 

 band of scales is an important adaptation for 

 the protection of this vital region against 

 attack from so fearful an enemy as the 

 lamprey. 



George Wagner. 

 Zoological Laboratory, 

 University of Wisconsin, 

 February 22, 1904. 



CURRENT NOTES ON METEOROLOGY. 



CLIMATE OF THE PHILIPPINES. 



In an article by Gannett on ' The Philippine 

 Islands and Their People,' published in the 

 National Geographic Magazine for March, 

 there are some notes on Philippine climate. 

 The mean annual temperatures are not far 

 from 80°, the range between the mean tem- 

 peratures of the warmest and coldest months 

 at Manila being but 7°. Temperatures of 

 100° are almost unknown. The lowest tem- 

 perature on record is 60°. The diurnal range 

 near the seacoast rarely exceeds 15°, and the 

 mean for the year is only 11°. The relative 

 humidity is always high, being usually at least 

 75 per cent. Erom November to June the 

 northeast trade, and from July to October the 

 southwest monsoon, is the prevailing wind. 

 Rainfall is much heavier on the windward 

 than on the leeward sides of the mountains. 

 In most parts of the islands the northeast 

 trade wind gives the dry season, and the south- 

 west monsoon brings the rains. The mean 

 annual rainfall varies between 40 and more 

 than 100 inches. At Manila, four flfths of 

 the annual rainfall comes between the first of 

 July and the end of October. Then the 

 streets are flooded, the air is saturated, and 

 things are covered with mould. 



CONDITIONS OF ATMOSPHERE DURING FOGS. 



In Das Wetter for January, Elias discusses 

 the conditions of the lower air during fogs, as 

 shown by kite observations at the Aeronaut- 

 ical Observatory near Berlin during the years 

 1901-2. The results are plotted to show the 

 variations in temperature, humidity and wind 

 with altitude. The most striking fact is that 



