The defense team of Casey Anthony started the 25th day's trial by calling an FBI geologist as its first witness.

The latest witness was Dr. Michael Sigman, chemistry professor at University of Central Florida. He testified this morning that air samples from Casey's car trunk showed traces of gasoline, chloroform and other volatile chemicals. He also found a chemical known to be used in degreasers or stain removers, according to the Orlando Sentinel.

The findings showed three chemicals, including chloroform, that have been associated with human decomposition, as well as cabbage and Chlorox. However, Sigman said these compounds gave very low responses in the instrument.

I cannot conclusively determine that the presence of those compounds indicated that there had been human remains in the trunk of the car, defense attorney Cheney Mason said, according to the Sentinel.

Casey Anthony, who is charged with killing her 2-year-old daughter Caylee, has pleaded not gulity. The prosecutors say Casey chloroformed Caylee and then put duct tape over her nose and mouth, suffocating the girl.

The first witness on Day 25 was geologist and forensic examiner Maureen Bottrell, who works in the FBI's Expert Trace Evidence Unit, the Sentinel said. Bottrell explained to the jury that her specialty involves examining rocks, soil, minerals and glass in criminal cases.

Bottrell testified that she examined the shovel that Casey Anthony borrowed from a neighbor and 22 pairs of shoes taken from the Anthony house in east Orange County. She said she found no materials from the trunk of Anthony's Pontiac Sunfire or shoes from her home that matched soil from her daughter's recovery scene.

Also, a shovel Casey borrowed from a neighbor was not tested for a comparison. But she agreed that the absence of soil on shoes is basically meaningless in establishing a person's presence or lack of presence at a scene.

The next witness was Madeline Montgomery, a forensic toxicologist for the FBI. She said she found no evidence of various drugs in hair from Caylee's recovery scene. All of her results were negative. The tests looked at 11 drugs, including Xanax, used to calm or put people to sleep.

But she also said she could not test the hair for chloroform and said a drug given to someone who then died soon after would not show up in the hair anyway, according to Orlando Sentinel.

Today's proceedings will be abbreviated as Chief Judge Belvin Perry has budget meeting for 9th Judicial circuit where he presides over.

Day 24 Trial

On Tuesday, prosecutors said a woman named April Whelan, jailed in a cell next to Casey Anthony, had a child who drowned in the family's pool in Orlando on Christmas Day 2007. Later, he was found by his grandfather. The incident is similar to the story given by defense lawyers for Casey Anthony.

The new piece in the jigsaw puzzle is being investigated, according to prosecutor Linda Drane Burdick. The prosecution believes that the woman in question, April Whelan, may not have told Casey the story of the child's drowning, but she may have heard it from other prisoners.

No jail records, investigations or reports indicate any contact between Casey and Whelan. But the dorm cells are not soundproof, and it is possible for conversations to be overhead, jail spokesman Allen Moore told Reuters.

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