Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
Charley Pike, the young son of a wealthy Ale baron, (played by Henry Fonda) describes himself as an "ophiologist." He is returning from a year's expedition up the Amazon which he says is the way he'd like to spend all his time - in the company of men like themselves in the pursuit of knowledge. The guys tell him to beware of the dames and he says "you know me, nothing but reptiles." This setup and any previous experience with romantic comedies should alert you to the fact that Charley is going to have nothing but trouble with dames. A bearded guy called Professor gives Charley a box with a snake in it. He tells him to feed it once a day - a couple of flies, a sip of milk, perhaps a pigeon's egg on Sunday and to keep her warm as he gets farther north and to sometimes let her out of her box to play a little. Sound scientific advice, all around - at least for a movie snake. Movie snakes always seem to eat things found in the kitchen like milk and eggs. He mentions professor Marsditz (wich is a scrambled version of Ditmars, the eminent herpetologist of that era) and says he has named the snake Colobrina marzditzia, which is described as a rare type of Brazilian Glass Snake. (It's played by a Long-nosed Snake - Rheinocheilus lecontei.)
Later we see Charley reading a book - Are Snakes Necessary? by Hugo Marzditz while all the young marriagable women in the ship's dining room try to get his attention, or as Barbara Stanwyck puts it - "Every Jane in the room is giving him the thermometer." Fonda takes her to his cabin to fix her broken shoe and warns her not to wake his snake named Emma which is as playful as a kitten. We see it later crawling on the bed. She asks him if he will always be interested in snakes? (A typical question from just about everbody - the assumption being that an interest in snakes or any reptiles and amphibians, is something for kids that adults normally grow out of.) He says "Snakes are my life, in a way." She says "What a life." After that this classic comedy by the great Preston Sturges goes completely downhill because there are no more snakes.