Microbiological testing apparatus

In a biological test tray having a plurality of chambers for carrying out tests of microorganisms in the presence of a plurality of different reagents in which the reagents are inserted into the chambers in a solution and then lyophilized to dryness, a microorganism is inoculated into each of said chambers and incubated for a predetermined period, and the activity of said microorganisms is read in an automatic reader, the improvement comprising

• A. a skirt around the periphery of the tray whereby a plurality of said trays may be stacked in a lyophilizer without closing said chambers,
• B. an orifice formed in at least two sides of said skirt whereby evacuation of sublimed moisture is enhanced, and
• C. cooperating fasteners defined on said skirt, whereby a plurality of said trays may be joined together for inoculation, incubation and reading.

A holder for a biological test card comprising

• A. a base
• B. retaining means comprising a pair of retaining arms of unequal width connected to said base adapted to receive a biological test card in only one orientation, and
• C. fastener means coupled to said base and extending outwardly from said base and adapted to cooperate with a biological test tray having cooperating fasteners defined on the skirt of said tray.