response to other visual and physical parameters during pre-oviposition stage and oviposition response to physical obstruction Dense vegetation is the main physical obstruction. The females of some species must pass through dense vegetation to approach their oviposition sites. IDOMAL:0002331 IDOMAL:0002331 The larval habitat of Uranotaenia anhydor at Saratoga Springs, California, was effetively subterranean. Egg rafts and larvae were foun only in pockets of water situated between clumps of the rush Scirpus. These were covered over so densely with mats formed from previous years' growth of rush that the water was in almost darkness. idomal_namespace