866 EXPERIMENT STATION EECORD. 



(A. maculatum), lone star tick (A. amencanum), cayenne tick (A. cajennense) , 

 rabbit Dermaceutor [Dennacentor parumapertus marginatus), Rocky Mountain 

 spotted-fever tick (D. vemistus), Pacific Coast tick (D. occidentalis), American 

 dog tick {D. rariabiUs) , and tropical horse tick (D. nit ens). 



A list of bibliographical references is appended. 



Rocky Mountain spotted fever, W. C. Ruckek {Puh. Health and Mar. Hosp. 

 Serv. U. S., Pub. Health Rpts., 27 (1912), No. 36, pp. i^65-^82).— This sum- 

 marized account includes a bibliography of 77 titles. 



The origin and sig'nificance of parasitism in the Acarina, H. E. Ewing 

 {Tram. Acad. Sci. St. Louis, 21 (1912), No. 1, pp. 70, pis. 8).— "We have very 

 strong evidence indicating that the parasitic habit has originated independently 

 at least 11 times in the phylogeny of the Acarina. Among the zoophagous 

 parasites the parasitic habit has been developed from 3 different tyi^es of free 

 living Acarina: (a) Predaceous forms, (b) scavengers, (c) forms living upon 

 the juices of plants. ... As is usually the case with other parasites, we 

 generally find here a gradual increase in the state of degenei'ation as we follow 

 the advancing stages of parasitism from its origin among free types. . . . We 

 find in the Acarina a process of degeneration which in its completeness is seldom 

 obtained in the animal kingdom." 



FOODS— HUMAN NUTRITION. 



Sewage-polluted oysters as a cause of typhoid and other gastro-intestinal 

 disturbances — a study of an epidemic and of certain individual cases, G. W. 

 Stiles (C/. 8. Dept. Agr., Bur. Chem. Bui. 156, pp. ^.'/, pis. .), figs. 7). — Accord- 

 ing to the author's conclusions from his investigations and a summary of data, 

 " there is undisputed evidence to show that infected oysters, clams, mussels, 

 scallops, and other shellfish may cause typhoid fever and other gastro-intestinal 

 disturbances when consumed by susceptible individuals. 



" The epidemics of typhoid fever, due to ingestion of polluted sea food, have 

 in most instances been traced to shellfish floated in polluted water, although 

 there is also evidence that oysters and other shellfish, grown in polluted waters 

 and directly consumed without transplanting for a time in pure waters, may be 

 the source of typhoid infection." 



A full account is given of investigations which led to the conclusion that 

 Rockaway oj'sters were wholly responsible for cases of typhoid fever and gastro- 

 enteritis (diarrhea) following a banquet. There were 17 well-defined cases 

 of typhoid fever, with 1 death, and S3 cases of gastro-euteritis traced directly to 

 such oysters from Jamaica Bay, floated at Indian Creek, near Canarsie, Long 

 Island, N. Y., with 10 additional cases of typhoid and 16 cases of diarrhea 

 traced to oysters from the same locality and in part from the same lot as those 

 furnished for the banquet. 



" This investigation comprises a complete study of all the factors which 

 would materially contribute to typhoid infection. Each item of the menu 

 served at the . . . banquet was carefully considered, and the Rockaway 

 oysters served were the only articles of food consumed by all of those who had 

 typhoid or gastro-enteritis following this banquet." 



Bacteriological studies showed sewage pollution in Jamaica Bay. and 

 " typhoid bacilli were isolated in pure culture after 7 and 21 days from oyster^; 

 which had been floated at Inwood, Long Island, N. Y., . . . and kept out of 

 water in storage at 39° F. Organisms of the Bacillus colt and B. paratyplwsus 

 groups were also isolated from oysters floated at Indian Creek. . . . They were 

 probably the cause of the gastro-enteritis cases following the . . . banquet." 



The diarrhea or bowel trouble referred to, according to the author's conclu- 

 sions, can probably be ascribed to the presence of paratyphoid bacilli (said by 



