21. The defect is located just superior to the tympano-mastoid suture line in the posterior ear canal. 22. My mother ( now 91 ) & her sister both had " mastoids " when they were young. 23. The mastoid bone is completely ossified, lacking the openings that are present in most species of the genus. 24. The splenius capitis is deep to sternocleidomastoideus at the mastoid process, and to the trapezius for its lower portion. 25. Although handicapped as a child by a double mastoid infection she took up the violin at the age of eight. 26. The " N " indicates that the polarity of the component is negative with respect to an average mastoid reference. 27. The insertion is at each rib, cervical and thoracic vertebrae, and all the way up to the mastoid process. 28. The skull of the African subspecies has a larger crest between the mastoid process and the jugular process of the exoccipital. 29. If left untreated, the cholesteatoma can erode into the mastoid process, producing mastoiditis, as well as other complications. 30. It is called the tympanic antrum, and must be distinguished from the mastoid cells, though it communicates with them.
