identify the bacteria to the species level. When species were indicated 

 as a result of differential procedures, they were recorded. 



The criteria used for the gram-positive rods and cocci were as outlined 

 in Harrigan & McCance (1966) and Cowan & Steel (1966) . Separation of 

 Staphylococcus aureus and S^. epidermus was based on coagulase activity. 

 Gram negative cocci were identified according to criteria set forth by 

 Collins (1967). 



The pigmented Gram-negative rods were identified from a scheme developed 

 from data from Hendrie, Mitchell & Shewan (1968) and Harrigan & McCance 

 (1966). The non-pigment ed, non-spore-forming Gram-negative rods were 

 identified from a determinative scheme based upon that of Shewan, Hobbs 

 & Hodgklss (1960) with additional information derived from Bain & Shewan 

 (1968), Collins (1967), Harrigan & McCance (1966), Baumann, Doudoroff & 

 Stainer (1968) and Cowan & Steel (1966) . Differentiation of the Enter- 

 bacteriaceae was according to Carpenter, Lepage & Steel (1966). Motility 

 was determined by direct observation of young broth cultures, 18-24 hr. 



The bacterial isolations obtained from and maintained on TSA medium was 

 tested on media prepared with distilled water while bacteria isolated on 

 Marine Agar was tested on media prepared with 30% Lyman and Fleming 

 (1940) synthetic sea water. Inoculated determinative media was incubated 

 at 32C. 



Mission Background . The first mission was 13 days in length with a crew 

 of four scientific and one engineer divers. They lived in the habitat 

 during the entire 13 days. This mission was treated as an isolated 

 mission as far as the microbiology program was concerned since there was 

 a six day refurbishment period between this and the next mission. 



The second, third and fourth missions were 20 days each; in tandom for a 

 total of 60 days. A crew change of the four scientific divers occurred 

 at the start of each mission. The engineer for mission 2 stayed through 

 the middle of mission 3, the new engineer stayed through the remaining 

 portion of mission 3 and all of 4. There were five divers on each crew 

 for a total of 14 for the three missions. The group of three missions 

 were considered a single operations phase for microbiological consider- 

 ations . 



The sixth mission started about 16 days after the completion of mission 

 4 and lasted 14 days. The crew composition was similar to mission 1. 

 There were a number of intrusions of press personnel during the first 

 and last days of the mission for a total of about ten days of crew iso- 

 lation. This mission will not be considered in detail for microbiolog- 

 ical purposes. 



The eighth, tenth and twelfth missions were similar in operation to 2, 3 

 and 4 and will be considered in the same manner. The fifteenth mission 

 was similar to mission 1 and will be considered accordingly. 



IX-39 



