840 



SCIENCE. 



[N. S. Vol. IV. No. 101, 



large number of 'short clams' {Venus merce- 

 naria) were brought into the laboratory to be 

 used in dissection. It was the plan of the in- 

 structors to harden a portion of these in such a 

 way that thick free-hand sections of the whole 

 animal could be made, thus to aid in demon- 

 stration of the anatomy. To accomplish this 

 result quickly, as we supposed, it was decided 

 to place them directly into commercial alcohol. 



About five dozen specimens were, therefore, 

 selected for this treatment ; one of the valves of 

 the shell of each was crushed, in order to allow 

 the fluid to penetrate freely into the mantle 

 chambers, and the whole number was then 

 placed in a large aquarium jar and covered 

 with 95 fo alcohol. This was at about eleven 

 o'clock in the evening of July 15th. The ma- 

 terial was not used on the next day, and so lay 

 undisturbed until ten o'clock of the day follow- 

 ing, i. e., July 17th, a period of not less than 35 

 hours. A series of thick sections was then 

 made by one of the students in the course, Mr. 

 N. B. Sloan, of Hillsdale College, and laid out 

 in a dish of fresh sea- water. In order to deter- 

 mine the sex of the specimen so treated, a bit 

 of the gonad was shown by him to be that of a 

 male, in which the sex cells were not only ma- 

 ture but were also showing their characteristic 

 movements in an unmistakable manner. The 

 attention of the instructors was called to this, 

 and the fact that the cells were alive was 

 tested by adding a drop of corrosive sublimate 

 at which all the movements quickly ceased. 



These germinal cells were toward the interior 

 of the visceral mass of the clam, and if the in- 

 fluence of the alcohol had reached them at all 

 through the investing sheath they were at least 

 able to resist it and to resume their normal 

 activities under the proper conditions. Whether 

 any of the somatic cells of the same tissues of 

 the animal were also living, such as the leuco- 

 cytes, was not tested, but even if no alcohol 

 had reached these germ cells, yet under the 

 adverse conditions, inasmuch as the ordinary 

 life processes of the animal had been so long 

 suspended, their vitality is remarkable. 



It may be, therefore, inferred that as they 

 reach maturity the spermatozoa of this lamelli- 

 branch may possess the ability of withstanding 

 many unusual conditions of the surrounding 



water into which they may be shed. But 

 whether it implies a long continued or a tem- 

 porary vitality was not sought by us ; nor was 

 it attempted to show by experiment whether 

 these sexual elements could withstand greater 

 chemical changes in the ordinary sea- water than 

 can the smaller marine Protozoa, for example. 

 It is certain, however, that as far as this species 

 is concerned, great promise is inherent in the 

 spermatozoa for obtaining the necessary distri- 

 bution. J, I. Peck. 



THE APPEARANCE OP THE MOON. 



To THE Editor of Science : The following 

 incident might supplement Mr. Brinton's inter- 

 esting account of the different pictures different 

 persons see in the moon. I was a member of a 

 jury in an important case a few months ago 

 and the members were much more than ordi- 

 narily intelligent. While out for a walk in 

 charge of the sheriff" one evening, the full moon 

 was coming over the hills to the east, and I 

 suggested that each man write down the im- 

 pression it gave him as to size. The slips were 

 deposited in a hat, and when drawn out the 

 comparisons ran from ' the size of a twenty-dol- 

 lar piece ' up to ' twelve feet. ' When near to 

 the horizon it struck me as being about eleven 

 inches across, and several put it about that, but 

 the thirteen men made it all sizes, four, six, ten 

 inches, three feet, five feet, etc. One man said 

 it was the size of a flour barrel and another of 

 a buggy wheel, etc. R. L. Fulton. 



Keno, Nevada. 



SCIENTIFIC LITERATURE. 

 Grundriss einer exacten Schopfungsgesichte. Von 



Hermann Habenicht. Vienna, Hartleben. 



No date. 136 pages, 7 folded plates. 



Habenicht has been for many years one of the 

 expert cartographers in the geographical estab- 

 lishment of Justus Perthes at Gotha. His com- 

 petent and sincere work in this exacting field 

 must secure him a courteous hearing if he has 

 anything to say about the world as a whole, so 

 much of which has come, at second hand, under 

 his fingers ; but in the collection of his essays 

 under the above title, the fruit of nearly forty 

 years of professional, morphological study of 

 the earth's surface, the deference that we owe 



