an allophone of (orthographic aa) which is realized as under the influence of uvular consonants, however this is not consistent for all speakers. The backness influence arises from articulation with uvular consonants and so the word kháa "person" is often spoken as , but the word (a) káa "on (its) surface" is said as by the same speakers. Word onset is always consonantal in Tlingit and so words never begin with a vowel. Where a vowel would theoretically have occurred, such as by prefixing or compounding, the vowel is always followed by either or . The former is universal in single words, and both are found in word-medial position in compounds. The orthography does not reflect the in word-initial position, but either . or y may be seen in medial position. For example: But when the perfective prefix ÿu- is word-initial, the glottal stop appears to ensure that the word begins with a consonant. Writing system Until the late 1960s, Tlingit was written exclusively in phonetic transcription in the works of linguists and anthropologists except for a little-known Cyrillic alphabet used for publications by the Russian Orthodox Church. A number of amateur anthropologists doing extensive work on the Tlingit had no training in linguistics and so left numerous samples in vague and inconsistent transcriptions, the most famous being George T. Emmons. However, such noted anthropologists as Franz Boas, John R. Swanton, and Frederica de Laguna have transcribed Tlingit in various related systems that feature accuracy and consistency but sacrifice readability. Two problems ensue from the multiplicity of transcription systems used for Tlingit. One is that there are many of them, thus requiring any reader to learn each individual system depending on what sources are used. The other is that most transcriptions made before Boas's study of Tlingit have numerous mistakes in them, particularly because of misinterpretations of the short vowels and ejective consonants. Accuracy of transcription can be increased by checking against similar words in other systems, or against a modern work postdating Naish and Story's work in the 1960s. Grammar Tlingit grammar at first glance appears to be highly fusional, but this is an incorrect assumption. There are predictable processes by which the basic phonetic shapes of individual morphemes are modified to fit various phonological requirements. These processes can be described with a regular language, and such descriptions are given here on a per morpheme basis by giving rule