June 1, 1906.] 



SCIENCE. 



847 



ting off the anterior end, including the so- 

 called eye-spot. When cut into halves, amphi- 

 oxus retained sensitiveness to light in the an- 

 terior half, but not in the posterior haK, 

 though the latter was normally reactive to 

 stimulation from very weak acid. This indi- 

 cates that though amphioxus is without a 

 brain proper, the anterior portion of its medul- 

 lary tube is related to the posterior portion 

 somewhat as the brain and cord are in the 

 higher vertebrates. The distribution of the 

 sensitiveness of amphiosus to light corre- 

 sponds to the distribution of the ' light ' cells 

 (Hesse) in its medullary tube and is probably 

 not connected with the skin. Specimens of 

 amphiosus tend to collect in the darker parts 

 of an aquarium. They also swim away from 

 a source of light. Amphioxus is, therefore, 

 negatively photodynamic and negatively pho- 

 totropic. 



The Relation of Blood Platelets to Thrombus 



Formation: Joseph H. Pratt. 



In frogs and rabbits experimental thrombi 

 three to ten minutes old were studied. In 

 the youngest thrombi there was agglutination 

 of blood platelets or spindle-cells and agglu- 

 tination of erythrocytes without evidence of 

 fibrin formation. The fusing and distortion 

 of the erythrocytes were marked. The ery- 

 throcytes were sometimes broken up into small 

 granular masses which simulated blood plates. 

 By the use of a sodium metaphosphate solu- 

 tion it was possible to distinguish the blood 

 platelets from the degeneration products of 

 the erythrocytes. 



On the Conditions of Bacterial Activity in 

 the Intestine in Cases of Advanced, Ap- 

 parently Primary, Anemias: G. A. Hertee. 

 The author reported results of the coor- 

 dinated studies of fifteen cases of apparently 

 primary advanced anemias, in ten of which 

 the blood picture was that of pernicious 

 anemia. The studies related to the occur- 

 rence of phenol in the urine and in the feces ; 

 of indol in the feces and indican in the urine; 

 of skatol in the feces; to the Ehrlich aldehyde 

 reaction of the urine; to the Ehrlich aldehyde 

 reaction of the feces; and to the hydrobili- 

 rubin reaction of Schmidt. In the case of 



indol, phenol and skatol, quantitative studies 

 were made. The observations established the 

 fact that in so-called primary pernicious and 

 allied anemias the indications of excessive 

 putrefactive decomposition are almost regu- 

 larly pronounced. These changes are asso- 

 ciated with definite and characteristic depart- 

 ures in the bacterial activity of the intestinal 

 fiora studied in fermentation tube experi- 

 ments. A careful study of the microscopical 

 fecal fields, of the sedimentary fields in fer- 

 mentation tubes, of the anerobic plates from 

 the sterilized feces, and of the results of a 

 modification of Welch's incubation test for 

 the gas-bacillus, indicates that in nearly every 

 instance examined the peculiar Saccharo- 

 butyric type of bacterial decomposition here 

 found is dependent upon B. Welchii (B. 

 aerogenes capsulatus). Evidence is further- 

 more brought forward to show that this or- 

 ganism is a prominent and perhaps specific 

 factor in advanced ' primary ' anemia. The 

 overgrowth of the gas-bacillus is associated 

 with a partial disappearance of B. coli. Dur- 

 ing convalescence the gas-bacillus recedes 

 numerically and B. coli resumes a dominant 

 position. 



Absorption of Typhoid Bacilli from the 

 Peritoneal Cavity: B. H. Buxton and J. 



C. TORREY. 



Shortly after injection of typhoid bacilli 

 into the peritoneal cavity of a rabbit the 

 organs in most experiments are found to be 

 invaded by the bacilli, more particularly the 

 liver and spleen, in which there may be enor- 

 mous numbers. By means of injection of 

 lamp black, the peritoneal path for this rapid 

 rush to the organs is shown to be by way of 

 the anterior mediastinal lymphatic trunks. 

 Even in five minutes after injection the 

 trunks and the anterior mediastinal lymph 

 nodes are markedly blackened. 



On plating out the lymph nodes after injec- 

 tion of typhoid bacilli, they are often found 

 to contain many millions of bacilli, and as a 

 general rule if there are many bacilli in the 

 lymph nodes there are also many in the 

 organs. 



