Circa 1912. This white Baggage has all the early features for this series, lacquered trucks held on by washers, flat, non-embossed truss rods, but has the automatic couplers, the car below has the orange and green roof and hook couplers.

The red Harvard / Yale cars came in two variations the very rare Rose color above and the later and more common red color below, Note that the doors are gray on the rose cars and yellow on the red ones. The gray litho under the red gave the Rose coloration.

The Blue variation is also difficult to find and was probably only manufactured between 1910 and 1912.  Below is an example in dark blue with painted gray trucks that match the roof.

Close up of a 1911 baggage in yellow. 

The yellow along with the red are probably the most common color variations this one is from 1912-1913 in that it has the automatic couplers and one piece roof

Circa 1915 - Here's one of those 'tweeners' - Limited Vestibule Express body, late T-truck frame, green litho door and green painted roof from the later green cars. Below is the red version, this one has the white baggage door with the green roof. To the best of my knowledge all baggage cars are marked LIMITED VESTIBULE EXPRESS.

Circa 1910-11, this white Yale car has hook couplers, shellacked trucks, flat truss rods and Limited Vestibule Express lettering. Same car below except with green center roof.

Close up of Blue No. 61 from 1912 - compare it to the darker blue car with gray trucks below.

A red Yale car Circa 1912-13 with hook couplers. This car is somewhat unusual in that it has the later lithography (The Ives Railway Lines), but hook coulers and non embossed frame. below is a similar car in the Rose variation but marked "Limited Vestibule Express".

Yellow Yale car Circa 1911 with hook couplers, flat truss rods and Limited Vestibule Express lettering. Below is a late version with one piece roof and "THE IVES RAILWAY LINES" lettering.

This red variation is circa 1912-13, note the lettering has changed to THE IVES RAILWAY LINES and although the frame on this one is still flat, this car can be found with an embossed frame.

Circa 1910-11, this white Harvard Car has shellacked trucks, hook couplers flat dk green frame and LIMITED VESTIBULE EXPRESS lettering. The car below has the orange and green roof.

Circa 1910-11 this is the Rose variation (note the gray doors), this one has a black frame and trucks. Another variation shown below has the lacquered trucks with an unusual brown/cream roof.

Blue Harvard car with black frame circa 1912. The yellow variation is below

Red variation Circa 1912-13, note automatic couplers, THE IVES RAILWAY LINES lettering and automatic couplers. Note the car below which is earlier and has white windows instead of the yellow below. This is due to one more layer of lithography.

Circa 1915, very late variation in yellow with solid one piece roof. Below is a side view

Circa 1913 - this car came with a set from 1913 - unusual combination of auto couplers, flat frame, one piece roof

Here's a complete Rose set in it's original rose red box. The early 25 is not the correct locomotive for this set.

Circa 1911 - This Empire State Express marked Lincoln under the windows is Not Ives but American Miniature Railway - look familiar.