The space in the thoracic cavity between the concave inner surfaces of the lungs, in which (in a special pericardial cavity) the heart is located, is called the mediastinum. The thoracic cavity is lined with a serous membrane called the pleura. The lungs are enclosed in the so-called pleural cavities, which are separate in man but communicate with one another in the majority of mammals. The shape of the thoracic cavity depends upon the shape of the thorax and the position of the diaphragm.
We sell 5 hammock sizes on the Traditional Hammocks (no spreader wood bars). Therefore, the length of the hammock is the same for each size but the difference is the width. Width gives the size. The larger the size, the wider and bigger the hammock.
Some are too small in the first place and all the hamsters can't fit on it at once. A syrian sized wheel or bigger is your best bet because a lot of the times your hamsters will want to run together. As well remember the key to success with wheels is having one wheel per hamster. * Now look at the water bottles.