Page 31. " ‘You hear the words inside your head?’ he asked "

The term telepathy was first used by the classical scholar Fredric W. H. Myers in 1882, to replace the original term ‘thought-transference’.

Telepathic individuals are theoretically able to read the thoughts and minds of others without the use of speech.

There has been much research done on the subject, but it is not currently accepted as fact by the scientific community.

Page 33. " Our men were better armed, too. Quite a lot of them had guns, whereas the Fringes people had only a few that they had stolen, and depended chiefly on bows, knives, and spears "
This is similar to the situation of the Native American people and the European settlers during the colonisation of America and the subsequent American Indian Wars that occurred intermittently between the two groups from 1622 to 1918, primarily over ownership of land.
Page 37. " His position, when a notification subsequently arrived stating that there was a recognized breed of tailless cats with a well-authenticated history, was awkward "
Manx breed cat named Inkku
Creative Commons Attribution Share AlikeManx breed cat named Inkku - Credit: Jonik

The Manx cat is a tailless breed that originated on the Isle of Man in the UK before 1700.

 

Page 40. " Ethics was why you should, and shouldn’t, do things "

Ethics is a branch of moral philosophy that seeks to answer questions about concepts such as right and wrong and good and evil.

     

Page 42. " the solonaceae as usual provided most of what there was "
Tomato (Solanum lycopersicum)
GNU Free Documentation LicenseTomato (Solanum lycopersicum) - Credit: Fir0002
Flowers of belladonna
Creative Commons Attribution Share AlikeFlowers of belladonna - Credit: Tom Oates

The Solanaceae family of flowering plants includes agricultural food plants such as potatoes, chilli peppers, tomatoes and aubergines. 

In addition, the family also has poisonous members including mandrake, deadly nightshade and tobacco.

Page 43. " I waded about fishing for the little shrimp-like creatures that lived there "
Gnathophausia zoea
GNU Free Documentation LicenseGnathophausia zoea - Credit: Alexander Semenov
These could well be Mysidacea, a group of small, shrimp-like creatures. They are also referred to as opossum shrimps, but are only distantly related to true shrimps.

Mysidacea can be found both in salt and freshwater, including in the Great Lakes of North America.

Page 49. " ‘This is for you, David,’ she said, putting it into my hand. I looked at it. A curling lock of brown hair, tied with a piece of yellow ribbon "

Arlington National Cemetery, Arlington House (Robert E. Lee Memorial), Robert E. Lee lock of hair
Creative Commons AttributionArlington National Cemetery, Arlington House (Robert E. Lee Memorial), Robert E. Lee lock of hair - Credit: Brad Holt
It was common practice in Victorian times and before to give locks of hair to a loved one as a token of remembrance or admiration.