Taxi Driver Still DetainedIn Probe Of Girl’s SlayinCobbie Explains Presence of Bloodstains on Trousers —Hope of Finding Victim's Clothing Fades—No New CluesAlthough he tentatively explained to the satisfaction of investigating officers the presence of bloodstains on his trousers, a taxidriver apprehended Sunday nightfor questioning in the slaying of Betty Jane Kennedy last Thursday was still being detained without charges at police headquarters last night.Detective Wayne Sellman said the taxi driver, who has a criminal record, asserted the bloodstains were caused by a passenger with a bloody nose.The trousers turned up yesterday at a local dry cleaning establishment.No New DevelopmentsInvestigators of the slaying fanned out in several directions yesterday but reported no new developments after a day of running down scores of tips and possible clues.The body of the youthful victim, for whom funeral services were held yesterday afternoon, was found Thursday morning in a clump of bushes along a road neart h e Maryland-Pennsylvania line.She had been strangled and her neck was broken.Another male suspect as well as several female acquaintancesof the suspected taxi driver were questioned yesterday.Chief of Police William H. Peters said the cabbie had been seenwith Miss Kennedy last Wednesday night on several occasions. The victim lierself had last been seen about 11 p, m. Wednesday night at a South Potomac street restaurant.Rope Owner SoughtPennsylvania State Police were attempting to find the owner of a piece of rope found about 300 yards from the spot near Rouzer-ville where her body had been discovered by a farmer. They said the rope might have been used by the killer to break the neck of his victim.Hundreds of persons visited the spot where the body was found over the weekend, while scores of curious persons viewed the body at a local funeral parlor. The funeral itself was not largely attended.Investigators reported last night that hope was fading that they might find the red dress, shoes and brassiere Miss Kennedy was wearing the night she was slain. The body was clad only in a pink slip when found.i (