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Feature-to-feature identification is made on simultaneous Ca It K-line spectrograms (SG) and K2v spectroheliograms (SHG). The line profiles in plages and in the network boundary nearly always have double-peaked reversal in the core, while those inside the cells present all possibilities: double-peaked, single-peaked on violet side, single-peaked on red side, and unreversed absorption. Statistics of the profiles in the quiet chromosphere show that 50 % are Kz32 double-peaked, 20 % are K2v single-peaked, 10 % are K2r single-peaked, and 20 % show oniy incipient reversal or even totally lack any reversal. We call attention to the nontrivial contribution of these absorption profiles which are formed in 'dark regions' shown on SHG's.The physical conditions inferred from different kinds of profiles are briefly discussed.