Gruesome and disturbing crime scene images of Caylee Anthony's skull with duct tape and strands of hair were shown in a Florida court Thursday.  Casey Anthony who is on trial for her little girl's murder was visibly shaken when the photos were shown.

FOX's Phil Keating reports from Orlando, Florida:

The crime scene photos with duct tape are a key part of the Prosecution's case.

Meanwhile, Casey's brother Lee was back on the stand Thursday describing a story Casey told him about how a 'nanny' took little Caylee.

Here is a summary of Thursday's Anthony trial proceedings from FOX News Producer Kathleen Reuschle who was in the courtroom:

Jurors saw the matted brown hair of two and a half-year-old Caylee Anthony, wound around her tiny, wet, white skull as it sat upright with leaves, roots and duct tape fabric intertwined around the jaw area.

The Prosecution admitted dozens of the crime scene photos into evidence that were taken after the toddler's remains were discovered on December 11, 2008 less than a half mile from the Anthony residence.

Judge Belvin Perry advised anyone who might feel queasy and emotional viewing such photos should leave.

The initial series of photos were taken by Jennifer Welch, the first crime scene investigator to respond to the area. You could see the top of the small skull next to a black plastic bag and an off-white canvas bag. You could also make out a piece of grey duct tape. The next series were taken by Steven Hanson, a Crime Scene Investigator from the Medical Examiner's office who came to photograph the scene and then collect the remains and evidence items for examination. You could see additional angles of the skull shown near a rotten log along with the surrounding items. One close- up photo in particular showed the skull embedded in the leaf bed so that only the eye socket and cranial area can be viewed. The grey duct tape is seen level with this eye socket area in the vegetation. The final photos were taken by Gary Hutz - the Deputy Medical Examiner and Forensic Pathologist who separated the items and photographed them individually back at the lab. This was the first time we saw the skull in its entirety photographed from various angles. In one photo in particular, you can see what looks like several pieces of duct tape around the front portion of the skull area. Another is taken from underneath the skull and you can see a 3-4 inch piece of tape extend along the bottom of the jaw stuck within a hair mat. Additional photos showed the fabric backing of the duct tape around this lower jaw area.

The Medical Examiner testified that it was very unusual to see remains at this stage of decomposition with the lower jaw bone still attached. It appeared to him that the combination of the hair mat, vegetation and possibly duct tape fabric fibers all kept the jaw together. He also pointed out a leg bone that could be seen inside a large bag the investigators collected everything in the area into.. laundry bag, black bag, twigs, leaves, dirt, vines and the small leg bone. Investigators also pointed out that a blanket, fabric remnants, a red Disney bag and shorts were among the remains. One of the last photos Jurors saw was of the little tattered striped shorts.

Casey Anthony refused to view the photos. Her attorneys set up barriers around the two monitors on their desks using their laptop screens and binders to block her view. She pulled her sleeves down and wrapped herself up in her white knit cardigan, silently crying and shaking slightly. She looked in her lap or at her arms, daring not to look up or make contact with anyone or anything. She breathed in deep and dabbed at her eyes.

Jurors kept a close eye on her and took extensive notes. The leaned closely into their monitors to view the photos and watched each witness closely. They remained unemotional and focused.

The day began with damning testimony from Lee Anthony who revealed Casey told him a completely new version of what had happened to Caylee when she bonded out from jail and was home for a period in August of 2008. She explained the "imaginary" nanny - so-called Zenaida Fernandez Gonzalez took Caylee from her when they were in Jay Blanchard Park. She claimed the woman held her down by her wrists and took her child to "teach her a lesson" for being an "unfit mother". In an even more bizarre admission Lee Anthony stated his sister told him this "nanny" was controlling Casey through her MySpace account and created a special password for her with the number 55 in it. Casey stated she believed this meant the nanny would release Caylee in 55 days - which would be by her birthday August 9th.

Interestingly meter reader Roy Kronk made his first call about finding the skull in the woods on August 11 yet the remains would not be uncovered until Dec. 11. The defense tried the bring this up in cross-examination but the judge asked Jose Baez to move on.

Defense attorneys focused most of their cross-examination raising doubt about the position the duct tape was found in when the small body was uncovered. They said several times the tape appeared "flat on the ground" or "in the air" Prosecutors must prove Casey Anthony sought to suffocate her daughter by placing the tape over her nose and mouth.

Casey sat through the day largely alone in her experience, with her Mother, Father and Brother electing not to be present for the gruesome and painful display. While she did not view the photos she could hear the extremely detailed descriptions of the condition her deceased daughter was found in. The photos kept coming and did not let up. When court returned from a mid-afternoon recess, Judge Perry announced "Miss Anthony was ill" and testimony would resume the next morning.