Ornithoid life form
Ornithoid life forms were an advanced, sentient ornithoid species from outside the Milky Way Galaxy. Without the amplification of their substantial mental abilities via their transmuter technologies, their tiny bodies and fragile physiology left them unable to survive in environments considered suitable for humanoids. 

Answering to the , two explorers from this species, Korob and , set up an observation outpost on Pyris VII during the mid-23rd century. They encountered the  and held members of the crew for study in 2267. Both died after James T. Kirk destroyed their means of support in an effort to escape capture. ()

In the 24th century, information about the species was used in schools as teaching aids in comparative xenobiology lessons. ()

In 2369, Jake Sisko was doing his homework on a PADD that featured two drawings of this species. ()

Later that year, a Bajoran student also had a PADD with drawings of the lifeform on his desk, which also featured a computer monitor with similar drawings. ()

Appendices

Background information 
The Ornithoids from "Catspaw" were represented by puppets, whose strings were clearly seen on screen. Their "puppet forms" were described in the script as "tiny creatures, wispy with the transparent skeins on jellyfish."
 
The image on the PADD was taken from the Star Fleet Medical Reference Manual, written by Geoffrey Mandel and illustrated by Doug Drexler. While not shown on-screen, the text of the manual indicates that the six horizontal circles are labeled A to F, the six vertical circles G to L, and identifies each letter as:
A - Optikos
B - Reflector
C - Gullet
D - Brain
E - Pulmos
F - Matrix Gland
G - Proboscis
H - Heart
I - Viscera
J - Nephros
K - Ovary
L - Crop

External link 
 Ornithoid Lifeform at the Alien Species Wiki 
Unnamed species
Lifeform classifications