August 30, 1964 pregnancies. (cont.) The development of the embryos is consistent with the full moon hypothesis. One roof rat was caught by hand the day traps were set on the south end of the island. Seven of the total of 11 rats caught on Runit were of the block phase, (Rattus rattus rattus). parts of the world. This phase occurs in many We found it rarely at Panope. [In my opinion, (Jackson's)--if memory is correct--this is the first time it has been recorded in the Marshalls. This block phase could have re- sulted from the introduction of an individual from a ship. ceivably, Con- it might be a mutant form induced by radiation. either case, why has it not been think the sampling was adequate, found on other islands? [In [I and I see no basis for believing that the Polynesian rat exists on this island. Gessel's notes on trip to Runit Island on EMBL boat: "Island has obviously been devastated and is in various stages of redevelopment. Apparently, wave deposition has been important in re-establishment land. of vegetation on this narrow is- Messerschmidia is predominant but very scattered, a few Scaevola, at least 1 Morinda and 1 Pandanus plant. A number of coconut trees in the old camp site and also near the tower. Fimbristylis and Triumfetta are very abundant, Euphorbia. as are species of