Number of students and annual variations

The register of attendance to Lamarck’s lecture courses on invertebrate zoology 
covers 29 years, from 1795 to 1823. From 1821 to 1823, as Lamarck become blind, 
Latreille gave lectures in his place. The register contains 1221 signatures.
 

However,

- The probable absence of a page for the year V (1797) has deprived us of 39 
positions in the register, though not necessarily of 39 signatures.
 
- 18 names have been cut out, perhaps by an autograph hunter

If we omit multiple inscriptions (students having attended lectures for more 
than one year), 973 appear to be the total number of individual participants. 
This may not be the final reckoning; doubts do indeed persist on unidentified 
signatures, or on possible different versions of the same name.
 

Yearly average attendance varies from 15 to 70. Two years stand out as 
exceptional; 1804, with 130 inscriptions, and 1805, with just 7. Whereas the 
possibility of mistakes made in the keeping of the register could not be ruled 
out, it is however clear that the years 1804, 1803, 1801 and 1802 were by far 
the most successful. Periodical variations probably due to historical 
contingencies are also noted: from 1811 to 1815, the yearly average fell to 26, 
a possible consequence of the Napoleonic wars. The period 1816-1820 registers an 
average of 51 students per year. Attendants from belligerent countries increased 
with the Restoration.