3.2 Local assimilations and syllabification rules 47reasonable way to derive it by assimilation from /dz/, which would be
perfectly pronounceable without change. Moreover, in the causative, where
only the cluster ts occurs in the stem proper, the Causative prefix allomorph is
-s- (or -s-) rather than -z- (e.g. PerfP -ass-stsa-), though -z- would be expected
if the lexical representation of the core stem contained Izl.3.2.1.4 zd —>zz, zd zz
Historically, there are indications of reductions of zd to zz and of zd to zz.
Perhaps in some cases the etymon had t instead of d. Compare (Imprt) azzay
'get to know' with Niger Tamajak "azday" (LTF2 367). This verb has now
merged formally, in Malian Tamashek, with (Imprt) azzay 'get well' (Niger
Tamajak "szzay"); cf. MGT 7.93. Likewise, compare (Imprt) azzaf'be black'
(Imprt) with e.g. abstractive nominal t-aessaettasf-t 'dark color; blackness', and
with Niger Tamajak forms based on consonant sequences Vstf and Vzdf (LTF2
384). In these cases, we get a transfer from the nongeminate type -vPQvC- to
the geminate -vPPvC- type, which has morphological consequences (different
shapes for long imperfectives, and for the VblN).
A case involving incomplete paradigmatic reassignment is (Imprt) Eezz
'weave', which corresponds to Niger Tamajak "äzdu" (LTF2 384, cf. MGT
7.119). The Tamashek PerfP is -azza-. Given such Imprt and PerfP forms, one
would expect LoImpfP #-t-dzz- on the model of LoImpfP -t-akk- for Imprt
sekk 'go', the other geminate -νΡΡυ- verb. Instead we get -zcitt- (all dialects),
showing an alternative consonantal sequence Vzt also seen in VblN t-e-zaete
(cf. Niger Tamajak "tezäte"). The t in -zdtt- and in t-e-zaete is evidently a
vestige of the alveolar stop in Niger Vzd.
'Mount (donkey) bareback' has Imprt azzam. Tamajak "szdam" (LTF2
384) shows that this is another case of *zd —> zz.
3.2.1.5 Prefixal t-Deletion
This rule is morphologically specialized. It applies clearly in combinations of
pronominal subject prefix t- (3FeSg or any 2nd person category) plus a
C-initial stem. Because perfective and inflectable short imperfective verb
stems begin with V's in most paradigms, the principal context for Prefixal
t-Deletion is with stems of the long imperfective family. Example with a
Lolmpf stem: 3MaSg i-sass 'he drinks', na-sdss or n-sdss 'we drink', but
3FeSg 0-sdss 'she drinks' and 2Sg 0-sdssae-d 'you-Sg drink'. It does not
matter what C the stem begins with. In addition to long imperfectives of
virtually all stem-classes, the rule also applies before inflectable short
imperfectives of causatives, which are also C-initial since they fail to undergo
Stem-Initial V-Insertion, hence 3FeSg ad 0-s-irad 'she will wash'. I use 0- to
indicate that Prefixal t-Deletion has occurred. There are also many adjectival