June 26, 1914] 



SCIENCE 



949 



series of acids, organic and inorganic, was 

 made and the results are given in the table 

 on p. 948. Pieces of the testis, a branched 

 filamentous organ, were placed in a n/100 

 concentration of acid and the time for color 

 change noted. In addition the partition 

 coefficients of the acids between xylol/water 

 was determined as a measure of the lipoid 

 solubility. Only a very few acids will pass to 

 xylol from w/100 concentration in water and 

 a few more from n/10 concentration. The 

 strength of the acid (after Ostwald), its effect 

 in lowering the surface tension of water (after 

 J. Traube) and its toxicity for cilia (studies 

 of my own carried out in Torres Strait) are 

 also included in the table. The acids are ar- 

 ranged in order of efficiency in each case. 

 Those with nearly the same effect or property 

 are tabulated in groups and in an order to 

 correspond as nearly as possible with the jpene- 

 tration series. An asterisk marks the acids 

 considerably out of place in each series as 

 compared with the penetration series. 



With the exception of benzoic and salicylic 

 all the acids encounter a resistance — small for 

 some, greater for others — at the cell surface. 

 If the tissue has previously been killed this 

 resistance is abolished and the cells become 

 readily permeable for all acids. The specific 

 permeability of tlie tissue for each acid is 

 therefore dependent on the living cells. 



It will be noted that there is no exact quan- 

 titative agreement between any two of the 

 series. The best agreement is between pene- 

 tration rate and toxicity; the worst between 

 penetration rate and degree of dissociation. 

 One may conclude that those acids are most 

 toxic which are able to penetrate the cell most 

 rapidly, a conclusion supported by my results 

 with alkalies. In neither case is there a rela- 

 tion between toxicity and dissociation. 



As regards the lipoid theory my results can 

 not be said to wholly support it; neither do 

 they wholly contradict it. The same state- 

 ment applies to Traube's Haftdruck theory. 

 There is a general relation between the power 

 to lower the surface tension of water (capillary 

 activity) and rate of penetration, but it is not 

 exact. With acids as with dyes and so many 



other substances, Overton's theory applies in 

 the majority of cases, but not in all. In my 

 opinion this can only mean that the power of 

 penetration of an acid depends on several 

 variable factors. One of these is lipoid solu- 

 bility or capillary activity, for the two run 

 more or less parallel, and a second is the 

 strength or affinity of the acid for certain pro- 

 tein substances of the cell surface. This 

 would explain the rather rapid penetration 

 of strong acids little soluble or insoluble in 

 lipoids. 



E. Newton Harvey 

 Princeton, N. J., 

 Apra 28, 1914 



A DESTRUCTIVB STRAWBERRY DISEASE 



Many of the long-distance strawberry ship- 

 ments of this season have suffered serious 

 injury culminating in a condition designated 

 by the consignees as " molds " or " leaks." 



In case of mold the berries, one or more per 

 box, often quite the whole contents of the box, 

 are more or less densely covered with a hairy 

 mold. 



The term " leak " designates a condition in 

 which a liquid issues copiously from the bot- 

 tom of the box. " Leaks " are accompanied 

 by a soggy condition of the berries which mat 

 down to occupy only one third or one fifth of 

 their original volume. 



The loss occasioned by these conditions is 

 very large and will in all probability reach 

 well into the millions this season. The berries 

 now so affected originate in Louisiana and 

 Mississippi. Data are not available concern- 

 ing conditions in other states. The conditions 

 mentioned have not occurred in previous years 

 to sufficient extent to attract the marked atten- 

 tion of the buyers or inspectors though it is 

 hardly to be supposed that they have been 

 entirely absent. 



The writer on April 30, acting for the Illi- 

 nois Central Eailroad, visited the berry region 

 of Louisiana to ascertain the condition, the 

 cause, and to render any assistance possible. 



A preliminary examination at Hammond, 

 La., May 1, of berries which had been in 

 refrigerators over night, which had been picked 



